Effectiveness of proximal tibial tubercle transfer in patients with patella baja after total knee arthroplasty

PURPOSE Patella baja after total knee arthroplasty (TKA) is a common problem that is usually treated via proximal transfer of the tibial tubercle. As the long-term outcomes of this procedure are unclarified, this study aimed to investigate the changes in clinical function and radiographic patellar height during five years of follow-up. METHODS Sixty patients with patella baja after TKA who underwent proximalisation of the tibial tubercle were followed up for a mean of 71 months (range 21-153 months). The pre- and postoperative range of motion (ROM) and clinical scores (Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)) were compared. The radiographic patellar height was measured with the Caton-Deschamps index (CDI), Blackburne-Peel ratio (BP), and modified Insall-Salvati index (MIS). RESULTS Proximalisation of the tibial tubercle resulted in a significant improvement in the ROM from 80° to 88°. The KSS and WOMAC did not improve or even worsened after the intervention. The radiographic patellar height immediately after tibial tubercle transfer was not better than prior to the intervention (CDI 0.72 vs. 0.63, p = 0.72; BP 0.66 vs. 0.61, p = 0.72; MIS 1.59 vs. 1.55, p = 1.00) and further decreased significantly so that the mean final values were worse than the values in the native joint (CDI 0.59 vs. 0.78, p = 0.001; BP 0.58 vs. 0.74, p = 0.001; MIS 1.39 vs. 1.81, p < 0.001). CONCLUSION Proximalisation of the tibial tubercle in patients with patella baja after TKA does neither lead to significant improvements in the clinical outcome nor in the radiographic patellar height during long-term follow-up. LEVEL OF EVIDENCE III

Akute Gefäßerkrankungen in der Gastroenterologie

Zusammenfassung: Vaskulär-gastroenterologische Notfälle zählen zu den häufigen Krankheitsbildern auf internistischen und chirurgischen Notfallstationen. Die klinischen Konsequenzen reichen von trivialen bis zu lebensbedrohlichen Situationen. Nur eine frühzeitige Erkennung der Symptomenkomplexe und die Anwendung der adäquaten diagnostischen Mittel führen zur korrekten Diagnosestellung mit nachfolgend - möglicherweise lebensrettender - Therapie. Um die hohen Mortalitätsraten der akuten Mesenterialischämien (50%), aortoenterischen Fisteln (30-40%), Aneurysmen viszeraler Arterien (10-100%) sowie des Budd-Chiari-Syndroms weiter senken zu können, gewinnen neue Strategien mit endovaskulärem Therapieansatz zunehmend an Bedeutung und ersetzen teilweise über viele Jahrzehnte etablierte Diagnose- und Therapiealgorithmen. Diese Übersichtsarbeit soll einen Überblick über aktuelle Diagnostik- und Therapiekonzepte häufiger vaskulär-gastroenterologischer Notfälle verschaffe

Die erschöpfende Reinigung von Aktin-Präparaten Zahl und Art der phosphathaltigen prosthetischen Gruppen von G- und F-Aktin

Exhaustive purification of actin preparations. Number and kind of phosphate containing prosthetic groups of G- and F-actin 1. 1. Previous investigations on the nucleoside phosphate content of G- and F-actin have all been carried out with unpurified or little purified protein preparations. It has never been tested whether the purification was complete or whether the purification itself inactivated the preparation. 2. 2. In F-actin solutions prepared according to Straub the content of adenine decreases by repeated ultracentrifugal sedimentation or Mg-precipitation according to Bárány to a constant level which is identical with both methods (16 μmoles/g protein). The adenine and phosphate content of the actin remains constant after the second purification procedure. Both procedures remove protein impurities present in the crude extract. 3. 3. The protein impurities are, however, not removed by repeated isoelectric precipitation of the crude unpolymerized Straub-extract. This procedure removes only contaminating phosphate and nucleoside phosphate of the crude extract. The actin polymerizes spontaneously during isoelectric precipitation. 4. 4. Ultracentrifugal sedimentation of F-actin, precipitation by MgCl2 or isolectric precipitation in presence of ATP do not inactivate the actin. The viscosity of F-actin, the ability for activating the ATP-ase of added L-myosin and the ATP-sensitivity of the resulting actomyosin remain constant even after repeating the purification procedure five times. 5. 5. Repeated isoelectric precipitation of actin in absence of ATP leads to an increasing loss of adenine phosphate and also to a stepwise decrease of Zν and ATP-sensitivity. 6. 6. In the nucleoside phosphate of purified F-actin the proportion of adenine to phosphate is 1:2 as in ADP. Paperchromatographic methods reveal in addition traces of AMP and ATP. 7. 7. G-actin and the contaminating proteins in the crude extracts contain also 16 μmoles adenine/g protein. 8. 8. From the content of adenosine phosphates bound to G- or F-actin (16 μmoles/g protein) the minimal molecular weight of the actin monomer is calculated as 62.000. 9. 9. The proportion adenine: phosphate and paperchromatographic methods show, that in the crude unpolymerized extract the protein-bound nucleoside-phosphate consists of 70–75% ATP and 25–30% ADP. Only 70–75% of the protein in the crude extract are able to polymerize. 10. 10. However, G-actin obtained from purified F-actin containing also 70–75% of its nucleoside phosphates as ATP does polymerize entirely. Thus whether or not ADP-G-actin polymerizes seems to depend on the history of the protein preparation. 11. 11. G-actin, whose ability for polymerization has been destroyed by X-rays, nevertheless activates the L-myosin-ATP-ase to a normal extent. The same holds for actin partly denatured by isoelectric precipitation in the absence of ATP. Thus, the ability of actin for polymerisation and its ability to activate the L-myosin-ATP-ase are independent properties. 12. 12. In phosphate or ATP containing solutions, purified F-actin ATP and inorganic phosphate reversibly (in addition to the tightly bound ADP). Howeever, actin is not phosphorylated in presence of ATP

The Effect of Patellar Positioning on Femoral Component Rotation when Performing Flexion Gap Balancing Using a Tensioning Device for Total Knee Arthroplasty

There is an increasing interest in new devices such as tensiometers for flexion gap balancing during total knee arthroplasty (TKA). The purpose of this study was to determine the influence of patella positioning during flexion gap balancing on femoral component rotation. We prospectively evaluated 32 consecutive knees in 31 patients who underwent primary TKA for degenerative osteoarthritis and where soft tissue balancing was performed using the same tensiometer. Preoperative measurements included valgus/varus deformation, mechanical axis, epicondylar axis, and tibial slope. Intraoperatively, measurement of femoral component rotation in 90 degrees of knee flexion was conducted in three different positions of the patella: (1) patella reduced, (2) patella dislocated but not everted, and (3) patella dislocated and everted. The femoral component had significantly higher rotation when the patella was reduced compared with a dislocated patella (4.9 ± 2.1 degrees vs. 4.2 ± 2.2 degrees; p = 0.006) and compared with a dislocated and everted patella (4.9 ± 2.1 degrees vs. 4.1 ± 2.3 degrees; p = 0.006). Varus knees (n = 22) demonstrated significantly increased femoral component rotation if the patella was reduced (5.3 ± 2.2 degrees) compared with dislocated patella without eversion (4.7 ± 2.3 degrees; p = 0.037) and with eversion (4.4 ± 2.5 degrees; p = 0.019). As such, the measurement of the mediolateral flexion gap stability with a laterally dislocated patella leads to a statistically significant overestimation of the lateral ligament stability and an underestimation of the external rotation positioning of the femoral component of approximately 1 degree, which is aggravated in varus knees. This is a Level II, prospective consecutive series study

Akute Gefäßerkrankungen in der Gastroenterologie

Acute gastroenterologic vascular emergencies are common situations in emergency departments and the clinical consequences range from trivial to life-threatening. Only the early recognition of these symptom patterns and prompt use of the appropriate diagnostic tools lead to a correct diagnosis with subsequent potentially life-saving treatment. To decrease the high mortality rate of acute mesenteric ischemia (50%), aorto-enteric fistula (30–40%), visceral artery aneurysms (10–100%) and Budd-Chiari syndrome new strategies with an endovascular approach are gaining importance and are partially replacing established diagnostic and therapeutic algorithms. This article provides a review of the diagnosis and therapy of these gastroenterologic emergency situations

Treatment of hindfoot and ankle infections with Ilizarov external fixator or spacer, followed by secondary arthrodesis

An established treatment strategy in surgical site infection after hindfoot and ankle surgery is a two-stage procedure with debridement and placement of a cement spacer, followed by antibiotic treatment and secondary arthrodesis. However, there is little evidence to favor this treatment over a one-stage procedure with debridement, followed by primary arthrodesis with an Ilizarov external fixator and antibiotic treatment. We compared the infection control and clinical and radiological outcome of a two-stage and a one-stage procedure. In this study, 7 patients with a two-stage revision and 11 patients with a one-stage revision between 2005 and 2015 were included. The primary outcome was infection control (absence of the Musculoskeletal Infection Society PJI criteria) 2 years after the ankle or hindfoot arthrodesis. Secondary outcome measures were the AOFAS hindfoot score and radiological consolidation rate. Infection control was 85% (6 out of 7 patients) in the two-stage group and 81% (9 out of 11 patients) in the one-stage group (p = 1.0). One patient (14%) of the two-stage and two patients (18%) in the one-stage group needed below-knee amputation. In the two-stage group, the mean postoperative AOFAS score was 74.8 (SD: ±11.3) versus 71.7 (SD: ±17.8) in the one-stage group. Radiological consolidation could be achieved in 71% in the spacer group (n = 5) and in 72% in the Ilizarov external fixator group (n = 9). Infection control, AOFAS score, and radiologic consolidation of hindfoot and ankle arthrodesis were comparable in both groups of patients with complicated postsurgical hindfoot or ankle infections. Keywords: ankle arthroplasty; arthrodesis; infection control; osteomyelitis; polymethylmethacrylate spacer

Innovation, value, and cost containment in shoulder arthroplasty

Background: The words “innovation” and “value” are generally not used in the same sentence when considering orthopedics. When used independently, however, it is evident that there has been no shortage of innovation within the field of orthopedics, especially in shoulder arthroplasty. Despite the abundance of innovations in shoulder arthroplasty prostheses and implants, it remains a challenge to identify whether there is apparent value associated with a given product. More often than not, new innovations are introduced with the promise of added value but prove to solely increase cost with no nominal outcome improvement. Objective: This article considers shoulder arthroplasty within the contexts of innovation, value, and cost. In order to define innovation, value, and cost, we look to the work of numerous experts and scholars in the fields of business, economics, and medicine. Our goal is to identify the shortcomings of current innovations in shoulder arthroplasty. Our purpose is to hold these innovations accountable for the holistic consideration of the value equation—namely, improved outcomes and reduced costs. The ideal innovation in shoulder arthroplasty shoulder offer tangible value to all stakeholders involved in the episode of care inclusive of patients, surgeons, insurers, and vendors/industry. Results: Under the premise that modern shoulder innovations are increasing in cost but have failed to demonstrate substantial improvements in patient treatment outcomes, we identify a number of key issues within shoulder surgery that remain: (1) better anatomical glenoid longevity, (2) better restoration of range of motion with reverse replacement, (3) reduced cost of implants, and (4) more transparency in outcomes. Conclusion: In order to qualify an innovation in shoulder arthroplasty which creates value, it must be backed by robust evidence-based studies that demonstrate the desired improved outcomes and reduced cost without any interfering biases

Current concepts in locking plate fixation of proximal humerus fractures

Despite numerous available treatment strategies, the management of complex proximal humeral fractures remains demanding. Impaired bone quality and considerable comorbidities pose special challenges in the growing aging population. Complications after operative treatment are frequent, in particular loss of reduction with varus malalignment and subsequent screw cutout. Locking plate fixation has become a standard in stabilizing these fractures, but surgical revision rates of up to 25% stagnate at high levels. Therefore, it seems of utmost importance to select the right treatment for the right patient. This article provides an overview of available classification systems, indications for operative treatment, important pathoanatomic principles, and latest surgical strategies in locking plate fixation. The importance of correct reduction of the medial cortices, the use of calcar screws, augmentation with bone cement, double-plate fixation, and auxiliary intramedullary bone graft stabilization are discussed in detail