Free subchondral screws in tibial plateau fractures: do they hinder a total knee arthroplasty? Strategies to prevent complications

Open reduction and internal fixation of extended lateral column tibial plateau fractures through a tibial condyle osteotomy and limited arthrotomy with the use of free subchondral locking screws is a straightforward and safe technique. However, these free subchondral screws are enclosed in the subchondral bone and therefore virtually impossible to remove after bone healing. The question arises whether these free subchondral screws might hinder a future total knee arthroplasty. In order to refute this, we retrospectively reviewed all surgically managed tibial plateau fractures in our tertiary center during one year and assessed the number, position and configuration of these in situ subchondral screws and K-wires. In addition, we performed a cadaver study, wherein we prepared 7 tibial plateaus for a total knee arthroplasty tibial component placement with free subchondral screws in situ. In this experiment, we demonstrated that free subchondral screws do not interfere with total knee arthroplasty, but they can increase operative time in some cases. We also provide recommendations to avoid difficulties and potential complications.

Why address posterior tibial plateau fractures?

Management of posterior tibial plateau fractures has gained much interest over the past few years. Fracture morphology, trauma mechanism, and soft-tissue injury have been identified as the key factors determining the treatment strategy and outcome. We provide a rationale for the operative management of posterior tibial plateau fractures by discussing the interplay between fracture morphology, trauma mechanism, and soft-tissue injury. The trauma mechanism has proven to be an important tool, not only to understand fracture morphology, but also to assess concomitant soft-tissue (i.e. ligamentous) injury. Subsequently, soft-tissue injury might play a role in future classification and diagnostic work-up of tibial plateau fractures, particularly in fractures with posterior involvement. Plate osteosynthesis using a posterior approach is safe and should be considered routinely in coronal fractures of the posterior tibial plateau, as illustrated.

Rates and determinants of antibiotics and probiotics prescription to children in Asia-Pacific countries

Antibiotic therapy may have important side effects. Guidelines recommend the administration of specific probiotics to reduce the risk of antibiotic-associated diarrhoea (AAD). The rates and determinants of antibiotics and co-prescription of probiotics in children remain poorly known in Asia-Pacific countries, which are very heterogenous in terms of economic development, health care organization and health policies. A survey among general practitioners (GPs) and paediatricians was performed in seven countries of the Asia-Pacific area (Australia, Japan, Indonesia, India, China, Singapore, and South Korea). Physicians completed an online questionnaire that explored their current habits and the determinants for prescribing antibiotics and probiotics. For the 731 physicians who completed the questionnaire (390 paediatricians and 341 GPs), 37% of all consultations for a child led to the prescription of antibiotics (ranging from 17% in Australia to 47% in India). A large majority of physicians (84%) agreed that antibiotics disrupted gut microbiota and considered probiotics an effective intervention to prevent AAD (68%). However, only 33% co-prescribed probiotics with antibiotics (ranging from 13% in Japan to 60% in South Korea). The main reasons for prescribing probiotics were previous episodes of AAD (61%), presence of diarrhoea (55%), prolonged antibiotic treatment (54%) or amoxicillin-clavulanic acid therapy (54%). Although current local guidelines recommend the use of selected probiotics in children receiving antibiotics in Asia-Pacific area, the rates of antibiotics and probiotics prescription significantly vary among countries and are deeply affected by country-related cultural and organisational issues.

No difference in mid-term survival and clinical outcome between patient-specific and conventional instrumented total knee arthroplasty: a randomized controlled trial

PURPOSE

The purpose of this multicentre prospective randomized controlled trial was to compare the survival rate and clinical outcome in total knee arthroplasty (TKA) after MRI-based patient-specific instruments (PSI) and conventional instruments 5 years after initial surgery.

METHODS

At a mean follow-up of 5.1 years (0.4), 163 patients (90.6%) with a mean age of 71.8 years (8.7) were analysed. A survival analysis with revision of the TKA as endpoint was performed. The Knee Society Score (KSS), evaluations on plain radiographs and patient-reported outcome measures (PROMs) were obtained preoperatively and at each FU.

RESULTS

At final follow-up, one TKA in the PSI- (1.2%) and 3 TKAs in the conventional group (3.8%) had undergone revision surgery (n.s.). No radiological abnormalities were noted at any time point. Postoperatively, the KSS and PROMs significantly improved within each group compared with the preoperative values. There were no clinically relevant differences for the KSS [PSI: 77.4, 9.8 (95% CI 75.0-79.7) vs. conventional: 77.3 10.5 (95% CI 74.9-79.8)] and the PROMs between both groups (n.s.) at 5 years follow-up.

CONCLUSION

There is still a lack of reliable data on the survival of TKA and clinical evidence, when using PSI for TKA. Longer follow-up studies are, therefore, needed.

LEVEL OF EVIDENCE

I.

Epidemiology of clavicle fractures in a level 1 trauma center in Belgium

PURPOSE

In the last 10 years, there has been an increasing tendency toward operative fixation of clavicle fractures. In this retrospective analysis, we will demographically assess all patients who sustained a clavicle fracture and were treated in our university hospital between 2004 and 2014.

METHODS

We retrospectively updated our database and analyzed all adult patients who were diagnosed with a clavicle fracture in our hospital. The following parameters were included in the database: age, gender, Robinson classification, date of trauma, injury mechanism, time until surgery, and reason for delayed surgery. Descriptive statistics were used to describe differences between patient groups and linear regression was performed to identify trends over time.

RESULTS

667 patients were included for analysis. The mean age was 43 ± 17.7 years. The majority of clavicle fractures occurred due to bicycle injuries (35.3%) and these increased from 2004 until 2014 (r = 0.738, R² = 0.545, p = 0.009). Patients with a midshaft clavicle fracture were increasingly treated primarily surgically (r = 0.928, R² = 0.861, p < 0.0001). There was an increased ratio of delayed surgery in relation to age from the age of 16 (9.1%) until the age of 70 years (37.2%).

CONCLUSIONS

There is an increasing number of fractures sustained by bicycle accidents and an increasing number of patients undergoing operative treatment. Middle-aged patients more often had delayed surgery compared with young adult patients. This could be due to an increased activity level of the elder population and the concomitant demand for a faster return to activities.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Functional outcome and economic burden of operative management of patellar fractures: the pivotal role of onerous implants

OBJECTIVES

The complication rate following operative treatment of patellar fractures remains high and is associated with a poor functional outcome. The primary goal of this study was to evaluate our functional outcome of patellar fracture osteosynthesis and define strategies to improve the outcome. The healthcare costs and utilization were calculated.

METHODS

All demographic, clinical, radiographic variables and hospital-related costs of 111 patients with 113 surgically treated patellar fractures between January 2005 and December 2014 were analyzed. Fractures were grouped as either simple or complex. Functional outcome was assessed using Knee Injury and Osteoarthritis Outcome Score (KOOS).

RESULTS

There were 67 simple fractures (59.3%) and 46 complex fractures (40.7%). The overall complication rate was 48.7%, including 19.5% implant-related complications. In 69 patients (61.1%), implants were removed. The outcome was rather poor, with considerable impairment in all KOOS subscales with the knee-related quality of life rated worst (median 62.5, IQR 37.5-81.25). Poor outcome correlated significantly with complex patellar fractures and extensive tension-band constructs.

CONCLUSIONS

The operative treatment of patellar fractures was associated with a high complication rate, functional impairment and reduced quality of life. Complex patellar fractures and extensive tension-band constructs were identified as the main determinants of poor outcome and increased economic burden due to higher reinterventions rates. Strategies to reduce complications and improve outcome should focus on less onerous implants.

Reamer-Irrigator-Aspirator bone graft harvesting for treatment of segmental bone loss: analysis of defect volume as independent risk factor for failure

INTRODUCTION

The management of segmental bone loss poses a significant clinical challenge. The purpose of this study was to conduct a retrospective evaluation of our experience in treating segmental bone loss, using Reamer-Irrigator-Aspirator (RIA)-harvested autologous bone graft.

MATERIALS AND METHODS

Between June 2008 and March 2015, 81 patients were treated with the RIA technique for multiple purposes. Inclusion criteria for this study were skeletal mature patients with segmental bone loss, due to acute trauma or non-union, who were treated with RIA-harvested bone graft. Exclusion criteria were skeletal immaturity, pathological fractures and indications for the RIA system other than bone graft harvesting. The primary outcome parameter was clinical and radiographical bone healing.

RESULTS

During the study period, 72 patients met the inclusion criteria. In total, 39 patients (54.2%) were classified as having clinical and radiographical bone healing. Although univariate analysis could not reveal any significant influence of specific risk factors to predict the outcome, there was a trend towards statistical significance for defect volume. Further analysis indeed revealed that smaller defect volumes (< 8 cm³) had a lower risk of non-union.

CONCLUSIONS

In approximately half of our study population, the use of the RIA technique for autologous bone graft harvesting in cases of segmental bone loss resulted in a successful outcome with bone healing. Defect size seems to be a critical issue regarding the outcome. Although our results are less promising than previously published, the RIA technique has its place in the treatment algorithm of segmental bone defects.

[Open reduction and internal fixation of lateral tibial plateau fractures with free subchondral 2.7 mm screws]

OBJECTIVES

Exact reconstruction of the depressed articular surface and stable subchondral fixation of the lateral tibial plateau (ORIF, "open reduction and internal fixation").

INDICATIONS

Tibial plateau fractures with involvement of the lateral column and depression of the articular surface.

CONTRAINDICATIONS

Critical soft tissue. Severe osteoporosis.

SURGICAL TECHNIQUE

Supine position, classical anterolateral approach, lateral submeniscal arthrotomy, visualisation of the fracture, osteotomy of the lateral tibial condyle. Reconstruction of the articular surface under visual control and temporary fixation with Kirschner wires. One or more 2.7 mm locking screws are placed subchondral for permanent stable fixation of the articular surface. If needed, the metaphyseal bone defect is filled with autologous or allogenic bone graft. The lateral tibial condyle is reduced and a 3.5 mm (variable angle) locking compression plate applied. Closure of fascia and skin in layers.

FOLLOW-UP MANAGEMENT

Free range of motion, in case of residual instability of the collateral ligaments varus-valgus stabilizing brace, partial weight-bearing of 10-15 kg for 8 weeks, control computed tomography (CT) scan after 3 months.

RESULTS

Since February 2014, a total of 23 lateral tibial plateau fractures were treated using the described technique; 4 patients were lost to follow-up and the 3‑month follow-up of 2 patients is not completed yet. After an average of 167 days, 11 patients had no complaints. At approximately 3 months postoperatively, 10 patients had full range of motion, 3 had a flexion deficit of at least 30°, and 2 patients had residual instability of the medial collateral ligament. One postoperative superficial infection was noted. At the 3 month CT, 10 of 17 patients showed successful reduction without significant articular steps or anatomical malalignment.

Intramedullary tibial nailing of distal tibiofibular fractures: additional fibular fixation or not?

INTRODUCTION

The anatomy of the distal tibia accounts for reduced biomechanical stability and higher complication rates when treating distal tibiofibular fractures with an intramedullary tibia nail (IMTN). The goal of this study was to identify variables that affect the stability of IMTN. We assessed the value of additional fibular fixation, angular stable interlocking screws (ASLS) and multiplanar screw configuration in IMTN.

PATIENTS AND METHODS

A retrospective cohort study was performed including 184 distal tibial fractures and associated fibula fracture treated with IMTN. Relevant demographic, fracture-related (type and level of the tibia and fibula fracture) and operative variables (depth of the nail, screw type and configuration, use of polar screws, fibular fixation) were studied. Coronal and sagittal alignment was assessed directly and 3-6 months after IMTN. Loss of reduction (LOR) was classified as 5-9° or ≥10°.

RESULTS

48.4% of the patients showed ≥5° LOR in one or both planes. Coronal LOR 5°-9° significantly correlated with low tibial fractures (p = 0.034), AO/OTA type 43 distal tibial fractures (p = 0.049), and sagittal LOR 5°-9° (p = 0.015). Although sagittal LOR 5°-9° was associated with fibular fractures (non-fixated suprasyndesmotic, p = 0.011), conversely we could not demonstrate the added value of (suprasyndesmotic) fibula fixation in IMTN. Coronal LOR ≥10° significantly correlated with AO/OTA type 43 distal tibial fractures (p = 0.009). In contrast to multiplanar configuration, we found a clear benefit of ASLS in distal IMTN locking.

CONCLUSIONS

The level of the tibial fracture (AO/OTA type) and (suprasyndesmotic) fibular fractures were the main determinants of LOR after IMTN. ASLS was found to increase the stability of IMTN. Due to heterogeneity, however, we could not demonstrate the value of fibular fixation in IMTN. Therefore, a future prospective study with uniform treatment strategy for IMTN of distal tibiofibular fractures, with or without fixation of the fibula, is mandatory.

Corrective limb osteotomy using patient specific 3D-printed guides: A technical note

We describe the step-by-step process of a corrective osteotomy using 3D printed patient specific guides. Before surgery, bilateral computed tomography (CT) scans are made to plan correction in the affected limb. The digital pre-planning defines the location of the K-wires, drill holes, and the osteotomy site(s). Subsequently, a 3D printed patient specific guide is applied, which indicates the exact position of these drill holes and the osteotomies. This increases the accuracy of the surgery by means of patient specific fit of the guide. During surgery an incision is made and the guide is applied on the bone, which allows the surgeon to perform a very precise osteotomy. Next, the bone is reduced either directly using the plate and marked drill holes, or indirectly using a second reduction guide. In the latter case, the previously drilled K-wires are used to adequately position the reduction guide. Fixation of the bone fragments using plating osteosynthesis finalizes the process. Although this technique has its specific limitations, it might serve as a powerful tool in the treatment of malunion of both articular and nonarticular fractures of the limb.

A revised 3-column classification approach for the surgical planning of extended lateral tibial plateau fractures

OBJECTIVES

Variable angle locking compression plates allow for lateral buttress and support of the posterolateral joint surface of tibial plateau fractures. This gives room for improvement of the surgical 3-column classification approach. Our aim was to revise and validate the 3-column classification approach to better guide the surgical planning of tibial plateau fractures extending into the posterolateral corner.

METHODS

In contrast to the 3-column classification approach, in the revised approach the posterior border of the lateral column in the revised approach lies posterior instead of anterior of the fibula. According to the revised 3-column classification approach, extended lateral column fractures are defined as single lateral column fractures extending posteriorly into the posterolateral corner. CT-images of 36 patients were reviewed and classified twice online according to Schatzker and revised 3-column classification approach by five observers. The intraobserver reliability was calculated using the Cohen's kappa and the interobserver reliability was calculated using the Fleiss' kappa.

RESULTS

The intraobserver reliability showed substantial agreement according to Landis and Koch for both Schatzker and the revised 3-column classification approach (0.746 vs. 0.782 p = 0.37, Schatzker vs. revised 3-column, respectively). However, the interobserver reliability of the revised 3-column classification approach was significantly higher as compared to the Schatzker classification (0.531 vs. 0.669 p < 0.01, moderate vs. substantial agreement, Schatzker vs. revised 3-column, respectively).

CONCLUSIONS

With the introduction of variable angle locking compression plates, the revised 3-column classification approach is a very helpful tool in the preoperative surgical planning of tibial plateau fractures, in particular, lateral column fractures that extend into the posterolateral corner. The revised 3-column classification approach is rather a practical supplement to the Schatzker classification. It has a significantly higher interobserver reliability as compared to the Schatzker classification, most likely due to the more simple nature of the revised 3-column classification approach.

A combined posterior reversed L-shaped and anterolateral approach for two column tibial plateau fractures in Caucasians: A technical note

OBJECTIVE

Open reduction and internal fixation of two column posterior and lateral tibial plateau fractures through a combined posterior reversed L-shaped and anterolateral approach in floating position in Caucasians.

INDICATIONS

Two column posterior and lateral tibial plateau fractures.

CONTRAINDICATIONS

Tibial plateau fractures that do not involve the posterior and lateral column.

SURGICAL TECHNIQUE

The patient is positioned in floating position, a reversed L-shaped skin incision is made, the posterior column after lateral retraction of the medial head of the gastrocnemius muscle is exposed, and the posterior fragments are reduced and fixed. Subsequently, flexion and varus stress on the knee is applied, an anterolateral skin incision is made, the lateral column is exposed, and the lateral fragments are reduced and fixed.

CONCLUSION

Despite a different physique as Asians, a combined posterior reversed L-shaped and anterolateral approach in a floating position for the surgical treatment of two column posterior and lateral tibial plateau fractures is technically possible in Caucasians. In our experience, this combined approach is an excellent strategy in most patients for surgical treatment of two column posterior and lateral column fractures.

Similar liver transplantation survival with selected cardiac death donors and brain death donors

BACKGROUND

The outcome of orthotopic liver transplantation (OLT) with controlled graft donation after cardiac death (DCD) is usually inferior to that with graft donation after brain death (DBD). This study compared outcomes from OLT with DBD versus controlled DCD donors with predefined restrictive acceptance criteria.

METHODS

All adult recipients in the Netherlands in 2001-2006 with full-size OLT from DCD (n = 55) and DBD (n = 471) donors were included. Kaplan-Meier, log rank and Cox regression analyses were used.

RESULTS

One- and 3-year patient survival rates were similar for DCD (85 and 80 per cent) and DBD (86.3 and 80.8 per cent) transplants (P = 0.763), as were graft survival rates (74 and 68 per cent versus 80.4 and 74.5 per cent; P = 0.212). The 3-year cumulative percentage of surviving grafts developing non-anastomotic biliary strictures was 31 per cent after DCD and 9.7 per cent after DBD transplantation (P < 0.001). The retransplantation rate was similar overall (P = 0.081), but that for biliary stricture was higher in the DCD group (P < 0.001). Risk factors for 1-year graft loss after DBD OLT were transplant centre, recipient warm ischaemia time and donor with severe head trauma. After DCD OLT they were transplant centre, donor warm ischaemia time and cold ischaemia time. DCD graft was a risk factor for non-anastomotic biliary stricture.

CONCLUSION

OLT using controlled DCD grafts and restrictive criteria can result in patient and graft survival rates similar to those of DBD OLT, despite a higher risk of biliary stricture.

Forequarter amputation for malignancy

Background

Forequarter amputation (FQA) is an important treatment for malignant disease of the shoulder girdle. The aim of this study was to elucidate its role in surgical oncology.

Methods

This retrospective study analysed 40 patients who had an FQA. In nine, the chest wall was resected. The most frequent diagnoses were soft-tissue sarcoma (28 patients) and recurrent breast cancer (five).

Results

Median follow-up was 16 (range 1–184) months. The 1-year, 2-year and 5-year overall survival for patients with malignant disease was 71, 59 and 38 per cent respectively. The median time to local recurrence (eight patients) was 4 (range 1–19) months. Thirty-two patients had curative FQA with a 1-year, 2-year and 5-year overall survival of 90, 75 and 48 per cent respectively, and a median overall survival of 51 months. The 5-year overall and disease-free survival for soft-tissue sarcoma was 41 and 26 per cent respectively. Eight patients had a palliative FQA with a median survival of 5 (range 1–12) months.

Conclusion

In locoregional disease such as sarcoma, FQA may offer the only possibility of cure. However, in patients with axillary metastasis, FQA has no impact on survival, although local control may improve the patient's quality of life.

Kinetic arrest and glass-glass transition in short-ranged attractive colloids

A thermally reversible repulsive hard-sphere to sticky-sphere transition was studied in a model colloidal system over a wide volume fraction range. The static microstructure was obtained from high resolution small angle x-ray scattering, the colloid dynamics was probed by dynamic x-ray and light scattering, and supplementary mechanical properties were derived from bulk rheology. At low concentration, the system shows features of gas-liquid type phase separation. The bulk phase separation is presumably interrupted by a gelation transition at the intermediate volume fraction range. At high volume fractions, fluid-attractive glass and repulsive glass-attractive glass transitions are observed. It is shown that the volume fraction of the particles can be reliably deduced from the absolute scattered intensity. The static structure factor is modeled in terms of an attractive square-well potential, using the leading order series expansion of Percus-Yevick approximation. The ensemble-averaged intermediate scattering function shows different levels of frozen components in the attractive and repulsive glassy states. The observed static and dynamic behavior are consistent with the predictions of a mode-coupling theory and numerical simulations for a square-well attractive system.

Multi length scale analysis of the microstructure in sticky sphere dispersions during shear flow

The effect of shear flow on the microstructure in a weakly aggregated suspension is investigated. Monodisperse small silica particles with a grafted layer of 1-octadecanol are dispersed in n-tetradecane, yielding a thermoreversible sticky sphere model suspension. A combination of small angle light scattering and ultra small and small-angle X-ray scattering techniques have been used, in situ and time resolved, to study the flow-induced anisotropy of the microstructure. In this manner, the length scales from the single particle size to that of the spatial organization of the aggregates can be covered. Harmonic expansion of the structure factor demonstrates that anisotropy develops in the microstructure on all relevant length scales. Possible real space interpretations of the scattering information are discussed in conjunction with implications for the nonlinear rheological behavior.

Modelling of microstructured waveguides using a finite-element-based vectorial mode solver with transparent boundary conditions

A finite-element-based vectorial optical mode solver is used to analyze microstructured optical waveguides. By employing 1st-order Bayliss-Gunzburger-Turkel-like transparent boundary conditions, both the real and imaginary part of the modal indices can be calculated in a relatively small computational domain. Results for waveguides with either circular or non-circular microstructured holes, solid- or air-core will be presented, including the silica-air Bragg fiber recently demonstrated by Vienne et al. (Post-deadline Paper PDP25, OFC 2004). The results of solid-core structures are in good agreement with the results of other methods while the results of air-core structure agree to the experimental results.

Inclusion of malignant fibrous histiocytoma in the tumour spectrum associated with hereditary non-polyposis colorectal cancer

Sarcomas, including the malignant fibrous histiocytomas (MFHs), are not known to be part of the tumour spectrum of hereditary non-polyposis colorectal cancer (HNPCC) as epidemiologically established. Therefore, occurrence of MFH in an HNPCC family may very well be coincidental. HNPCC is associated with germline mutations in DNA mismatch repair genes, including the MSH2 gene. We analysed an MFH diagnosed in a 45-year-old male HNPCC patient carrying a germline MSH2 mutation for HNPCC-associated molecular characteristics, to investigate a possible relationship between the tumour and that mutation. DNA analysis revealed microsatellite instability and loss of one MSH2 copy, and immunohistochemistry showed absence of nuclear MSH2 protein staining. To investigate whether this is a common finding in MFH, microsatellite instability and nuclear MSH2 protein staining was tested for in 5 and 6 sporadic MFHs, respectively. None showed microsatellite instability and all stained positively for MSH2. Together, these findings show that in rare cases, MFH may be part of the HNPCC tumour spectrum.

Lactobacillus GG administered in oral rehydration solution to children with acute diarrhea: a multicenter European trial

BACKGROUND

The probiotic Lactobacillus GG is effective in promoting a more rapid recovery of acute, watery diarrhea in children with rotavirus enteritis. Very limited information is available, however, on the potential role of such agents in non-rotaviral diarrheal episodes. Furthermore, no evidence is available concerning the efficacy of Lactobacillus GG administered in the oral rehydration solution during oral rehydration therapy. A multicenter trial was conducted to evaluate the efficacy of Lactobacillus GG administered in the oral rehydration solution to patients with acute-onset diarrhea of all causes.

METHODS

Children 1 month to 3 years of age with acute-onset diarrhea were enrolled in a double-blind, placebo-controlled investigation. Patients were randomly allocated to group A, receiving oral rehydration solution plus placebo, or group B, receiving the same preparation but with a live preparation of Lactobacillus GG (at least 10(10) CFU/250 ml). After rehydration in the first 4 to 6 hours, patients were offered their usual feedings plus free access to the same solution until diarrhea stopped.

RESULTS

One hundred forty children were enrolled in group A, and 147 in group B. There were no differences at admission between the groups in age, sex, previous types of feeding, previous duration of diarrhea, use of antibiotics, weight, height, weight-height percentile, prevalence of fever, overall status, degree of dehydration, and percentage of in- versus outpatients. Duration of diarrhea after enrollment was 71.9 +/- 35.8 hours in group A versus 58.3 +/- 27.6 hours in group B (mean +/- SD; P = 0.03). In rotavirus-positive children, diarrhea lasted 76.6 +/- 41.6 hours in group A versus 56.2 +/- 16.9 hours in groups B (P < 0.008). Diarrhea lasted longer than 7 days in 10.7% of group A versus 2.7% of group B patients (P < 0.01). Hospital stays were significantly shorter in group B than in group A.

CONCLUSIONS

Administering oral rehydration solution containing Lactobacillus GG to children with acute diarrhea is safe and results in shorter duration of diarrhea, less chance of a protracted course, and faster discharge from the hospital.

Protein synthesis rate measured with L-[1-11C]tyrosine positron emission tomography correlates with mitotic activity and MIB-1 antibody-detected proliferation in human soft tissue sarcomas

Protein synthesis rate (PSR) can be assessed in vivo using positron emission tomography with L-[1-11C]tyrosine (TYR-PET). Biological activity of soft tissue sarcomas (STS) can be measured in vitro by the mitotic rate and number of proliferating cells. In STS the grade of malignancy, in which the mitotic index plays a major role, is considered to be the major standard in predicting biological tumour behaviour. This study was designed to test the validity of TYR-PET in relation to different histopathological features. In 21 patients with untreated STS, the PSR was measured using TYR-PET. The number of mitoses was counted and tumours were graded according to the grading system of Coindre et al. (Cancer 1986; 58:306-309). Proliferative activity was assessed by immunohistological detection of the Ki-67 nuclear antigen using MIB-1 monoclonal antibody. To test the association between the PSR and these tumour parameters, a correlation analysis was performed. A significant (P<0.05) correlation was found between PSR and the Ki-67 proliferation index (R = 0.54), and between PSR and mitotic rate (R = 0.64). There was no correlation between PSR and tumour grade. The present study in malignant soft tissue tumours relates in vivo tumour metabolism as established with TYR-PET to tumour activity measured in vitro and indicates that the non-invasive method of TYR-PET can estimate the mitotic and proliferative activity in STS.

Povidone-iodine liposomes--an overview

In recent years, liposomes have been increasingly explored as novel drug delivery systems, and several liposome-based drug products have been approved in Europe, the USA and Japan. Depending on size, composition and surface characteristics, liposomes interact specifically with biological structures. Liposomal drug products provide a topical activity at the desired locus of action and are deemed more effective and less toxic than conventional drug formulations. The combination of povidone-iodine (PVP-I) and liposomes unites the exceptional microbicidal activity of the antiseptic substance with the excellent tolerability and lack of immunogenicity of liposomes; in addition, liposomes provide a moist molecular film for the wound environment. The multilamellar vesicles act as microreservoirs hence prolonging the release of the active ingredient. Although no commercial product for repeated application on the eye is currently available, PVP-I has been used in ophthalmology not only for pre- and postoperative antisepsis, but also for the treatment of bacterial and viral conjunctivitis and for prophylaxis against ophthalmia neonatorum. For these indications, liposomal formulations with 2.5 and 5.0% PVP-I were developed. These eye drops are isotonic with tear fluid at pH 6. First in vitro tests demonstrated an excellent antimicrobial efficacy, and a placebo-controlled clinical study on volunteers showed a very good local tolerability. A study on rabbits demonstrated positive results of the PVP-I liposome eye drops compared to placebo and the broadspectrum antibiotic Polyspectran in a standardized model of Staphylococcus aureus deep eye infection. The other aim is a well-tolerated liposomal PVP-I hydrogel for improved antiseptic wound treatment with moisturizer. It has been reported that liposomes are enriched at the wound bottom for direct action against infection and support of wound healing. An animal study on the efficacy and tolerability of different formulations of a hydrogel with PVP-I liposomes in deep dermal burn wounds has indicated an outstanding quality of wound healing with smooth granulation tissue, less inflammation, less wound contraction and no hyperkeratotic reactivity, especially with the 3% PVP-I liposome formulation.

Improving the palatability of oral rehydration solutions has implications for salt and water transport: a study in animal models

It is believed that improving the taste of oral rehydration solutions (ORSs) might lead to greater patient acceptability. A pilot trial showed that replacing glucose with sucrose and increasing the citrate concentration at the expense of chloride improves palatability. However, the transport implications of such modifications are not known. Three hypotonic experimental ORSs (Suc/cit-ORS, 211 mosmol/kg; Suc/Cl-ORS, 224 mosmol/kg; and Glu-ORS, 224 mosmol/kg) were compared with a standard European ORS (Euro-ORS, 265 mosmol/kg) by in vivo perfusion of entire rat small intestine in normal adult rats and rotavirus-infected neonates. All ORSs were of identical sodium, potassium, chloride, and citrate content except that in the Suc/cit-ORS, chloride was removed in favor of increased citrate, and the chloride concentration in Euro-ORS was higher than in the others. Suc/cit-ORS and Suc/Cl-ORS had glucose partially replaced by sucrose while Glu-ORS and Euro-ORS contained only glucose. In normal small intestine, water absorption was greater from Glu-ORS than Suc/cit-ORS or Euro-ORS, although water absorption was similar from Suc/cit-ORS and Suc/Cl-ORS. In the rotavirus model, Glu-ORS produced more water absorption than Euro-ORS or either sucrose ORS. In both models, Suc/cit-ORS caused sodium and chloride secretion. Glucose absorption was similar from all ORSs. These findings indicate that attempts to improve ORS palatability by adding sucrose or increasing citrate at the expense of chloride would incur a significant penalty in terms of salt and water absorption.

Reconstruction of human skin from glycerol-preserved allodermis and cultured keratinocyte sheets

The aim of this project was to reconstruct human skin from glycerol-preserved dermis and layers of cultured keratinocytes for use in the treatment of deep burns and ulcers. Glycerol-preserved cadaver skin from the Euro Skin Bank was treated with Dispase II or PBS, under various conditions, to find the best method of retaining the physical structure of the dermis while removing the epidermis and remnants of dead dermal cells which might provoke an allogeneic reaction in a graft recipient. Monoclonal antibodies LH39 and LH7.2, with specificity for basement membrane determinants, showed that treatment with Dispase II resulted in separation of the epidermis from the dermis with concomitant loss of all cellular elements from the dermal layer (as judged by H and E staining). However, when sheets of cultured keratinocytes were applied to the treated dermis and cultured for several days, the keratinocytes attached and regenerated a new basement membrane.

Collaborative study of the International Office of Cocoa, Chocolate and Sugar Confectionery on Salmonella detection from cocoa and chocolate processing environmental samples

A comparative collaborative study was performed in 13 laboratories to evaluate the use of motility enrichment on Modified Semisolid Rappaport-Vassiliadis medium for rapid Salmonella detection from food-processing environmental samples. Artificially contaminated chocolate scrapings and naturally contaminated cocoa bean dust samples were used in the study. Pre-enrichment was performed in buffered peptone water with added casein and malachite green oxalate. Motility enrichment was compared with a conventional cultural procedure using Rappaport-Vassiliadis broth and selenite cystine broth as selective enrichment. The productivity of motility enrichment was 93.5% compared to a productivity of the cultural procedure of 92%. Statistical analysis showed that there was no significant difference between the two procedures. Modified Semisolid Rappaport-Vassiliadis medium is a sensitive and simple diagnostic tool for the microbiological safety evaluation of food-processing environments.

Are complications in intraoperative radiation therapy more frequent than in conventional treatment?

To evaluate whether intraoperative radiation therapy (IORT) results in higher complication rates than conventional radiotherapy, 119 patients were studied who entered four prospectively randomized clinical trials that compared IORT with conventional therapy. Malignant neoplasms included 33 gastric carcinomas, 35 retroperitoneal sarcomas, 22 resectable pancreatic cancers, and 29 unresectable pancreatic cancers. One hundred thirty-six complications developed among 66 patients who received conventional therapy, and 108 complications developed among 53 patients who received IORT. There was no statistical significance between treatment groups with respect to the overall incidence of complications. Analysis of types of complications by tumor type using Fisher's exact test revealed only one significant complication: an increased rate of sepsis among the patients with retroperitoneal sarcoma who received conventional therapy compared with their IORT cohorts. The overall complication rate associated with IORT was equivalent to conventional radiotherapy in the treatment of these malignant neoplasms and supported the use of IORT where clinically indicated.

Delivery of intraoperative radiation therapy after pneumonectomy: experimental observations and early clinical results

Intraoperative radiation therapy (IORT) is capable of delivering high doses of radiation to mediastinal structures while sparing lung parenchyma, heart, and other locoregional tissues. A canine model of pulmonary resection and IORT was investigated by performing a pneumonectomy in 15 adult foxhounds followed by 0 cGy, 2,000 cGy, 3,000 cGy, 4,000 cGy. No clinical complications developed in 4 animals in the 2,000-cGy group. However, 2 of the 8 animals given a high dose died of esophageal hemorrhage or carinal necrosis. Esophagitis occurred in 10 of 12 animals, and none of the animals experienced bronchial stump dehiscence. In a limited Phase I protocol, 4 patients with non-small cell lung cancer were treated with resection and 2,500 cGy of IORT to two separate ports encompassing the superior and inferior mediastinum. Two patients experienced life-threatening bronchopleural fistulas, and 2 patients died as a consequence of esophageal problems. One patients had recurrence with brain metastases, and the 1 long-term survivor is free from disease. As opposed to the animal model of thoracic IORT, the clinical study demonstrated major toxicity with respiratory and esophageal morbidity. The therapeutic usefulness of thoracic IORT in the management of lung cancer must be questioned in view of this small but consistent series of patients. Further carefully designed clinical studies using lower doses of IORT are needed.

Pathological tissue changes following intraoperative radiotherapy

Ninety patients with a variety of advanced-stage malignancies were treated with surgical resection, when feasible, and with intraoperative radiotherapy. Certain patients received additional external beam radiotherapy. During clinical follow-up, 45 patients died. Twenty-two patients (49% of deaths) underwent detailed autopsies between 1 and 18 months after treatment, with special attention directed towards assessing radiation damage to various tissues. Histological changes related to radiation were generally manifested as fibrosis. Mild fibrotic changes in retroperitoneal soft tissues and mild hypocellularity in vertebral bone marrow were consistently present in patients treated for pancreatic carcinoma, gastric carcinoma, and retroperitoneal or pelvic sarcomas. Fibrosis of the soft tissues of the porta hepatis without narrowing of the bile duct was present in patients treated for pancreatic or gastric cancer. perineural fibrosis was present in retroperitoneal and pelvic nerve trunks in patients treated for abdominal or pelvic sarcomas and in patients treated for unresectable carcinoma of the pancreas. Significant radiation-related changes were generally not observed in major blood vessels, intestine, or ureter. Intact irradiated primary tumors consistently displayed necrosis.