Merging cross-border flow optimization techniques for performance maximization.

Both FARCROSS and TRINITY EU research projects aim to increase cross-border electricity flow and regional cooperation. The integration of SmartValve and T-SENTINEL systems offers benefits such as enhancing grid security and reliability, managing thermal constraints, and maximizing utilization of existing infrastructure. The combined system can achieve a more efficient and less costly coordinated network security process, increase cross-border capacities, and promote regional electricity market integration, benefiting the local communities with significant CO2 emissions avoidance and reduced electricity prices. Overall, the integration of SmartValve and T-SENTINEL can provide significant improvements in flexibility, making cross-border connections more robust and adaptive to the evolution of the electrical power industry.

Use radiography rarely, not routinely, for hip hemiarthroplasty.

PURPOSE: Hip hemiarthroplasty (HA) is a commonly performed operation. A post-operative radiograph forms part of the routine hip fracture pathway, although patients are often mobilised prior to this investigation. This study seeks to provide evidence for a pragmatic clinical change to optimise patient safety and allocate limited resources within the National Health Service (NHS). METHODS: We undertook a retrospective database review of 1563 HA procedures to assess whether the routine ordering of check radiographs played an important role in a patient's post-operative care. RESULTS: 18 (1.2%) mechanical complications led to a return to theatre within 6 weeks of the index procedure. All were dislocations. Ten had a normal post-operative radiograph and five had documented suspicion of dislocation prior to radiography. The post-operative check radiograph was the sole identifier of dislocation in only three patients (0.2%). All three of these patients were pre-morbidly bed bound and non-communicative due to cognitive impairment (AMTS 0/10). CONCLUSION: Unless a patient is pre-morbidly bed bound and cognitively impaired, routine post-operative radiography following HA surgery is of little clinical benefit, yet may carry considerable risk to the patient and cost to the NHS. A pragmatic compromise is to perform intra-operative fluoroscopic imaging.

Utility of Transbronchial Biopsy in the Immunocompromised Host With New Pulmonary Radiographic Abnormalities.

OBJECTIVE: To assess how often transbronchial biopsy (TBBx) added unique positive findings apart from other synchronous bronchoscopic sampling techniques including the bronchoalveolar lavage-immunocompromised host (BAL-ICH) panel that justified changes in management in an array of immunocompromised patients with new pulmonary radiographic abnormalities. METHODS: We retrospectively reviewed all bronchoscopies performed at Mayo Clinic Rochester between January 2012 and December 2017; on the basis of the physician's selection of a BAL-ICH panel, we identified 192 immunocompromised patients who underwent bronchoscopy with both a BAL-ICH panel and TBBx. The results of the BAL-ICH panel and TBBx were compared and subsequent management decisions analyzed from clinical notes. We identified changes in immunosuppressive agents, antibiotics, chemotherapy, goals of care, and decisions on further evaluation and procedures. We assessed whether the TBBx findings added information not identified on the BAL-ICH panel and other bronchoscopic sampling methods performed during the same procedure that justified subsequent management changes. RESULTS: Of 192 bronchoscopic procedures performed on immunocompromised patients with acute and subacute pulmonary radiographic abnormalities, management changes justified by the unique positive results of the TBBx occurred 28% (51/192) of the time. Those immunocompromised by solid malignant neoplasms and receiving active immunosuppressive therapy had management changes justified 62.1% (18/29) of the time by the TBBx results. No additional fungal organisms were identified on TBBx that were accounted for on the BAL-ICH panel. CONCLUSION: Transbronchial biopsy may add information to other bronchoscopic findings in immunocompromised patients, especially those with solid malignant neoplasms receiving active immunosuppressive treatment. These potential benefits must be weighed against the risks inherent to the procedure.

A rare case of chemotherapy induced phrenic neuropathy.

BACKGROUND: While chemotherapeutic agents result in an improvement in both disease-free and overall survival in cancer patients, treatment can result in short and long-term complications. One well-known complication is neuropathy which can result from a number of chemotherapeutic agents. However, chemotherapy-induced phrenic neuropathy is an exceedingly rare phenomenon with few cases reported in the literature. CASE: A 34-year-old male with metastatic testicular cancer presented with progressive dyspnea on exertion after initiation of chemotherapy with bleomycin, cisplatin, and etoposide. Multiple diagnostic studies were performed including pulmonary function testing, chest computed tomography, fluoroscopic sniff evaluation, in addition to phrenic nerve electromyography. Based on results of these tests, the diagnosis of chemotherapy-induced phrenic neuropathy was made. CONCLUSION: Chemotherapy-induced phrenic neuropathy, although rare, should be considered as a cause of dyspnea in cancer patients following initiation of chemotherapy.

The posterior acetabular wall (PAW): an aid to acetabular orientation at primary THA.

INTRODUCTION: Incorrect acetabular component positioning during total hip arthroplasty (THA) may lead to dislocation, impingement, wear and revision. Surgeons commonly use the transverse acetabular ligament (TAL) as a landmark for acetabular component orientation. The posterior acetabular wall (PAW) is a structure easily viewed on plain radiography and its position can help guide acetabular component position. In this study, we examine the efficacy of preoperative radiographs in predicting cup position relative to the PAW. METHODS: Prospective data was recorded on radiographic findings of the posterior wall (prominent, normal, deficient) on a consecutive series of 200 primary THAs utilising a standardised posterior approach. The final cup position relative to the wall was recorded (prominent, flush, deep). Cup inclination and version were then assessed by postoperative radiography and any instances of dislocation recorded. RESULTS: There were 117 females and 83 males with a mean age of 66.5 years. 154 were recorded as having a normal PAW on radiographs, 152 had the cup positioned in line with the TAL and flush to the PAW. 29 had a deficient PAW and 27 of these had a cup positioned prominently with 17 having a prominent PAW and of these 16 a deep cup position. Postoperative radiographs showed a mean cup version of 20.8° and inclination of 44.7° using this method. There were 21 outliers (10.5%) with no dislocations at a minimum 12-month follow-up. CONCLUSIONS: The TAL is a continuation of the posterior labrum. As such, the posterior wall is a useful adjunct to and surrogate landmark for the TAL. It has the added advantage that it is visible on radiographs and so aids surgical planning with respect to cup positioning.

Novel use of a trabecular metal spacer in the treatment of a long-standing ulnar fracture non-union.

The use of trabecular metal (TM) implants in spine and joint surgery is well documented. However, their use has yet to be reported as an alternative to either allograft or autograft in the management of fracture non-unions. We present our experience in using a TM implant for treating a patient with a long-standing ulnar fracture non-union. Excision of devitalised bone resulted in a 17 mm defect which the TM implant was used to infill. The defect was then bridged with a locking plate. At 2-year clinical and radiographic review, bony union and a pain-free return to full function was noted. In this case, the use of a TM implant avoided the morbidity associated with an iliac crest autograft.

Huntingtin fragments and SOD1 mutants form soluble oligomers in the cell.

Diffusion coefficients of huntingtin (Htt) fragments and SOD1 mutants expressed in cells were measured using fluorescence correlation spectroscopy. The diffusion mobilities of both non-pathological Htt fragments (25 polyQs) and pathological Htt fragments (103 polyQs) were much slower than expected for monomers suggesting that they oligomerize. The mobility of these fragments was unaffected by duration of expression or by over-expression of Hsp70 and Hsp40. However in cells with HttQ103 inclusions, diffusion measurements showed that the residual cytosolic HttQ103 was monomeric. These results suggest that both non-pathological and pathological Htt fragments form soluble oligomers in the cytosol with the properties of the oligomers determining whether they cause pathology. SOD1 with point mutations (A4V, G37R, and G85R) also had slower diffusional mobility than the wild-type protein whose mobility was consistent with that of a dimer. However, the decrease in mobility of the different SOD1 mutants did not correlate with their known pathology. Therefore, while soluble oligomers always seem to be present under conditions where cell pathology occurs, the presence of the oligomers, in itself, does not determine the extent of neuropathology.

Hip stability after ligamentum teres resection during surgical dislocation for cam impingement.

PURPOSE: The purpose of this study was to investigate whether patients who have undergone surgical hip dislocation with excision of the ligamentum teres exhibited symptoms of a Type I ligamentum teres rupture. METHOD: A questionnaire was designed to enquire about specific symptoms attributed to Type I injuries (complete rupture) in the literature: gross instability, incomplete reduction, inability to bear weight and mechanical symptoms. 217 consecutive patients were surveyed and 161 patients (75%) returned 168 questionnaires (75%). Mean age was 34 and median follow-up was 51 months (35 to 97). RESULTS: All patients were able to fully weight bear after surgery while 77% experienced no groin pain and 61% experienced no pain on exercise. 35% of patients experienced popping and locking in their operated hip and 24% had subjective feeling of their hip giving way. CONCLUSION: Patients who have had surgical excision of the ligamentum teres during open osteochondroplasty for cam deformities do not exhibit symptoms of a Type I ligamentum teres rupture. Our results show that minor instability symptoms may be present but symptoms present more like to Type II (partial) injuries. We propose that Type II injuries be divided into Type IIa; partial tear and Type IIb; iatrogenic rupture.

Judet osteoperiosteal decortication for treatment of non-union: the Cornwall experience.

BACKGROUND: The treatment of non union can be challenging with a variety of surgical options available to achieve bone consolidation. Robert Judet first described a method of osteo-periosteal decortication in 1963. He stated that by elevating cortical chips that remain attached to the periosteum and overlying soft tissues surrounding the site of non-union, combined with mechanical support, the bone consolidated. Despite excellent results presented in 2008 of 99% union rates with a mean delay of 8 months, the technique has not yet become popularised. We aim to show that Judet's method of decortication can achieve good results in the management of failure of union in a hospital other than Judet's. METHODS: Retrospective analysis was performed from December 2002 to December 2008 of 40 cases in 39 patients of osteoperiosteal decortication for fracture non-union. Concurrent stabilisation was with internal fixation only. All procedures were performed by one surgeon (MN) using the Judet technique after learning the technique in the originators hospital. A preoperative non union scoring system was also used to assess its use in predicting persistent non-union. RESULTS: Union was successfully achieved in 36 of the 39 surviving cases (92.3%) after a median delay of 8 months (range 3-47, SD 9.2) Twenty-six patients (65%) achieved union following the decortication procedure without subsequent operations. Factors such as open fracture and smoking did not have a statistically significant effect on union. The mean number of procedures following decortication was 0.68 (range 0-4). Metalwork failure occurred in 11 cases (28%), the majority in femoral decortications (n=9, 82%). The femur was the site of all persistent non unions in the series. Three patients had superficial infections and two had deep infections. The pre-operative non union scoring system (0-100) means were noticeably worse for the persistent non union group 42.0 (20-46) compared with the union group 31.0 (range 4-52). CONCLUSIONS: Osteoperiosteal decortication remains a highly effective surgical technique in the management of failed fracture union. The non union scoring system is a reliable predictor of persistent non union after this type of surgery. CLINICAL RELEVANCE: Relevant to general trauma orthopaedic surgeon and specialist orthopaedic surgeons with an interest in fracture non-union.

Hip resurfacing arthroplasty in patients with varus deformity of the femoral neck-shaft angle.

Hip resurfacing arthroplasty (HRA) in patients with a varus deformity of the femoral neck-shaft angle (NSA) is associated with poorer outcomes. Our experience has not reflected this. We examined the Oxford Hip Scores (OHS), Harris Hip Scores (HHS) and outcomes of patients with varus hips against a normal cohort to ascertain any significant difference. We identified 179 patients. Measurement of the femoral neck-shaft angle was undertaken from antero-posterior radiographs pre-operatively. The mean NSA was 128.5 degrees (SD 6.3). Patients with a NSA of less than 122.2 were deemed varus and those above 134.8 valgus. These parameters were consistent with published anatomical studies. The 'varus' cohort consisted of 23 patients, mean NSA 118.7 (range 113.6-121.5), mean follow-up 49 months (range 13-74). Mean OHS and HHS were 16 and 93.5 respectively. Complications included 2 cases of trochanteric non-union, but there were no femoral neck fractures, early failures or revisions. The 'normal' cohort consisted of 125 patients, mean NSA 128 degrees, mean follow-up 41 months (range 6-76). The OHS and HSS were 18.8 and 88.9 respectively. Complications included 5 trochanteric non-unions and 1 revision due to an acetabular fracture following a fall. Statistical analysis demonstrated no statistical difference between the cohorts' OHS (p=0.583) or HHS (p=0.139). Our experience in patients with a varus femoral neck has been positive. We have not yet experienced any femoral neck fractures, which we believe is in part due to the use of an uncemented femoral component and preservation of blood supply.

NMR method for measuring carbon-13 isotopic enrichment of metabolites in complex solutions.

Isotope-based methods are commonly used for metabolic flux analysis and metabolite quantification in biological extracts. Nuclear magnetic resonance (NMR) spectroscopy is a powerful analytical tool for these studies because NMR can unambiguously identify compounds and accurately measure (13)C enrichment. We have developed a new pulse sequence, isotope-edited total correlation spectroscopy (ITOCSY), that filters two-dimensional (1)H-(1)H NMR spectra from (12)C- and (13)C-containing molecules into separate, quantitatively equivalent spectra. The ITOCSY spectra of labeled and unlabeled molecules are directly comparable and can be assigned using existing bioinformatics tools. In this study, we evaluate ITOCSY using synthetic mixtures of standards and extracts from Escherichia coli . We show that ITOCSY has low technical error (6.6% for metabolites ranging from 0.34 to 6.2 mM) and can detect molecules at concentrations less than 10 muM. We propose ITOCSY as a practical NMR strategy for metabolic flux analysis, isotope dilution experiments, and other methods that rely on carbon-13 labeling.

Femoroacetabular impingement and classification of the cam deformity: the reference interval in normal hips.

BACKGROUND AND PURPOSE: Most patients with femoroacetabular impingement (FAI) have a cam deformity, which may be quantified by measuring the alpha angle and anterior offset ratio (AOR). Knowledge of what constitutes a "normal" alpha angle and AOR is limited. We defined the reference intervals of these measurements from normal hips in the general population. PATIENTS AND METHODS: 157 individuals from the general population were reviewed clinically and radiographically. 74 individuals with clinical evidence of hip disease or radiographic evidence of osteoarthritis (OA) were excluded, leaving a study group of 83 individuals (mean age 46 (22-69) years, 44 females) with normal hips. The alpha angles and AORs were measured from cross-table lateral radiographs taken in 15 degrees internal rotation. A validation study consisting of a cadaver study and a measurement reliability study was also performed. RESULTS: The mean alpha angle was 48 degrees in men and 47 degrees in women. The mean AOR was 0.19, the same in men and women. Thus, sexes were combined to derive 95% confidence intervals for the population mean alpha angle (46-49 degrees ) and AOR (0.18-0.20). The 95% reference interval for the alpha angle was 32-62 degrees degrees, and for the AOR it was 0.14-0.24. The validation study confirmed that these measurements were resistant to a reasonable degree of variation in positioning and that the repeatability and reproducibility of the measurements was good. INTERPRETATION: These reference intervals indicate that clinically and radiographically normal hips may have alpha angles and AORs that have previously been considered "abnormal". The thresholds provided by this study will aid classification of individuals involved in longitudinal studies of FAI and OA, and may be of use to the practicing clinician in evaluating the young adult with hip pain.

Non-union following bilateral simultaneos Ganz trochanteric osteotomy.

Between January 2003 and December 2004, 13 patients underwent bilateral resurfacing arthroplasty via a Ganz trochanteric osteotomy. This bilateral group was mobilised fully weight-bearing with crutches. During the same period 139 Ganz trochanteric osteotomies were performed for unilateral hip resurfacing. These patients were mobilised with crutches, weight-bearing up to 10 kg on the operated leg. Nine osteotomies (32%) in the bilateral group subsequently developed a symptomatic non-union requiring revision of fixation. This compares with 10 patients (7%) in the unilateral group. Applying the Fisher's exact test, the difference reached significance (P=0.0004). In two patients a second revision was required to achieve union. In one patient, revision of trochanteric fixation precipitated a deep infection. Protected weight-bearing following a Ganz trochanteric osteotomy is important to the success of the procedure. Simultaneous bilateral hip arthroplasty through a Ganz approach should be avoided. If it is undertaken, we recommend that patients should be non weight-bearing for 6 weeks following surgery. Non-union following a Ganz trochanteric osteotomy for arthroplasty carries a significant morbidity.

Early failure of the Dual coat Cormet 2000 metal on metal acetabular component.

We report a 10% failure rate for aseptic loosening and overall revision rate of 15% at 5 years mean follow up in 190 patients using the Cormet 2000 Dual coat acetabular component. Between 2001 and 2004, the original Dual coat component was used in our region by 4 experienced arthroplasty surgeons. 142 were used with resurfacing heads. The average age was 54 and 99 were male. Revision for aseptic loosening was required in 20 cups (10%) at a mean interval of 23 months including five within 2 months. Persistent groin pain was seen in a further three patients who have declined further surgery. Failure of the backing of this implant to integrate reliably with bone has led to an unacceptably high early loosening rate of the original design which was phased out in 2003.

Open surgery for hip impingement.

Mechanical impingement of the proximal femur against the acetabular rim is now recognized as a common cause of labral tears and degenerative changes in the hip. Open surgery is successful in treating this condition if damage to the articular cartilage surface is minimal.

Metal-on-metal hip resurfacing: the effect of cup position and component size on range of motion to impingement.

The aim of this dry bone study was to determine the range of hip motion to impingement for different hip resurfacing cup positions and component sizes. The maximum angles of hip flexion, extension, abduction, and adduction were calculated from 3-dimensional coordinates for: 1. Cup inclination of 30 degrees , 40 degrees , 50 degrees , 60 degrees , and 70 degrees with fixed anteversion; 2. Cup anteversion of 0 degrees , 10 degrees , 25 degrees , 35 degrees , and 45 degrees with fixed inclination; and 3. 3 different component sizes on the same size dry bones. An acetabular component inclination of 50 degrees and an anteversion of 25 degrees allowed the most physiologic range of hip motion. A larger-diameter femoral component relative to the native femoral neck diameter resulted in a greater range of hip motion to impingement.

Femoral oxygenation during hip resurfacing through the trochanteric flip approach.

Femoral neck fracture is one of the most common complications of hip resurfacing and considered by some to be related to reduced blood flow as a consequence of the surgical approach. We measured oxygen concentration during hip resurfacing through the trochanteric flip approach (n = 15 patients) and compared this approach with previous data for the posterior and anterolateral approaches. With the trochanteric flip the average femoral oxygenation decreased during the procedure to approximately 50% of that at the start, however it recovered to starting level by the end of the procedure. Preservation of oxygenation with the trochanteric flip was similar to that observed with the anterolateral approach, but with less variation during the procedure. Both of these approaches were superior in terms of oxygenation preservation to the posterior approach which resulted in a dramatic reduction in oxygenation.

Clathrin adaptor GGA1 polymerizes clathrin into tubules.

GGAs, a class of monomeric clathrin adaptors, are involved in the sorting of cargo at the trans-Golgi network of eukaryotic cells. They are modular structures consisting of the VHS, the GAT, hinge, and GAE domains, which have been shown to interact directly with cargo, ARF, clathrin, and accessory proteins, respectively. Previous studies have shown that GGAs interact with clathrin both in solution and in the cell, but it has yet been shown whether they assemble clathrin. We find that GGA1 promoted assembly of clathrin with complete assembly achieved when one GGA1 molecule is bound per heavy chain. In the presence of excess GGA1, we obtained the unusual stoichiometry of five GGA1s per heavy chain, and even at this stoichiometry the binding was not saturated. The assembled structures were mostly baskets, but approximately 10% of the structures were tubular with an average length of 180 +/- 40 nm and width of approximately 50 nm. The truncated GGA1 fragment consisting of the hinge+GAE domains bound to clathrin with similar affinity as the full-length molecule and polymerized clathrin into baskets. Unlike the full-length molecule, this fragment saturated the lattices at one molecule per heavy chain and assembled clathrin only into baskets. The separated hinge and GAE domains bound much weaker to clathrin than the intact molecule, and these domains do not significantly polymerize clathrin into baskets. We conclude that clathrin adaptor GGA1 is a clathrin assembly protein, but it is unique in its ability to polymerize clathrin into tubules.