Ten-year follow-up and clinical outcome of a metaphyseal anchoring short hip stem prosthesis: a retrospective single-centre analysis.

PURPOSE: Short stems for total hip arthroplasty are an alternative to traditional conventional long stems. Short stems are designed to facilitate minimal-invasive surgery, improve bone-stock preservation, and mimic a physiological load distribution. However, there is little evidence of the long-term outcome of short stems. This study aims to analyze the ten year survival rates and clinical outcome of one specific metaphyseal short hip stem implant. METHODS: We retrospectively analyzed the patient records of the patients who underwent a total hip arthroplasty with a monoblock partial collum sparing metaphyseal short hip stem prosthesis in 2008 and 2009 in our clinic. Patients were contacted, and clinical follow-up was recorded using the German version of the modified Harris Hip Score. Furthermore, complications, revision surgery, and post-operative radiographs were analyzed. RESULTS: Data from 339 primary implantations in 322 patients were retrieved. The mean follow-up was 10.6 years. Seven patients underwent a revision. The ten year survival rate with any revision surgery as the endpoint was 97.5%. The mean modified Harris Hip Score was 86 points (range 30 to 91 points). Five patients had an intraoperative fracture of the femur (1.6%). Two patients (0.6%) had a dislocation of the hip. The stem tip-to-cortex distance, measured in the anterior posterior view, was 2.6 mm (range 0 to 8.3 mm). CONCLUSION: The ten year survival rate of our used monoblock partial collum sparing metaphyseal short hip stem implant is comparable to traditional stems for total hip arthroplasty.

The timing of tether breakage influences clinical results after VBT.

INTRODUCTION: Tether breakage is a frequent mechanical complications after vertebral body tethering (VBT), but not all patients with a breakage show loss of correction. The reason of this clinical finding has not yet been clarified. We hypothesized that the integrity of the tether is relevant only in the early stages after VBT, when it drives growth modulation and tissue remodelling. After these mechanisms have taken place, the tether loses its function and a breakage will not alter the new shape of the spine. Thus, tether breakage would have a greater clinical relevance when occurring shortly after surgery. METHODS: All consecutive patients who underwent VBT and had a min. 2-year follow-up were included. The difference in curve magnitude between the 1st standing x-ray and the last follow-up was calculated (ΔCobb). For each curve, the presence and timing of tether breakage were recorded. The curves were grouped according to if and when the breakage was observed (no breakage, breakage at 0-6 months, 6-12 months, > 12 months). The ΔCobb was compared among these groups with the analysis of variance (ANOVA). RESULTS: Data from 152 curves were available: 68 with no breakage, 12 with a breakage at 0-6 months, 37 at 6-12 months and 35 > 12 months. The ANOVA found significant difference in the ΔCobb among the groups (Sum of square 2553.59; degree of freedom 3; mean of square 851.1; Fisher test 13.8; P < 0.0001). Patients with no breakage or breakage at > 12 months had similar ΔCobb (mean 4.8° and 7.8°, respectively, P = 0.3), smaller than the 0-6 or 6-12 groups (15.8° and 13.8°, respectively). CONCLUSION: Tether breakage leads to a consistent loss of correction when occurring within the first 12 months, while it has limited clinical relevance when occurring later on.

[Treatment strategies for pathological fractures of the spine]. / Versorgungsstrategien bei pathologischen Frakturen der Wirbelsäule.

BACKGROUND: Pathological fractures and instabilities of the spine are most often caused by primary tumors that hematogenously metastasize into the spine. In this context breast, prostate, kidney cell and bronchial carcinomas are the most relevant causative diseases. Furthermore, multiple myeloma is another frequent entity. Primary tumors of the spine are correspondingly rare and only make up a small proportion of all malignant processes in the spine. DECISION MAKING: The main symptom of pain is prognostically unfavorable in this context and is often associated with progressive instability or pathological fractures. To objectify the treatment approach the neurological status, an oncological assessment, the biomechanical stability and (systemic) general condition (NOMS criteria) of the patient have to be considered. Another major factor is the radiation sensitivity of the tumor. The spinal instability neoplastic (SIN) score is recommended to assess stability. Regardless of whether conservative or surgical treatment is carried out, interdisciplinary cooperation between the specialist departments must be guaranteed in order to achieve adequate treatment for the patient. TREATMENT: If a curative approach is followed an individualized and interdisciplinary surgical strategy must be performed to achieve an R0 resection, usually as a spondylectomy. In the case of palliative treatment, the goal of surgical treatment must be pain reduction, stability and avoidance or restoration of neurological deficits. This requires stabilization in a percutaneous or open technique, possibly in combination with decompression and local tumor debulking.

[The gut microbiome in Parkinson's disease]. / Das Darmmikrobiom bei der Parkinson-Krankheit.

The vast majority of Parkinson's disease (PD) cases are of sporadic origin and despite extensive research in recent years, the etiology still remains unclear. Several current case control studies are aiming to characterize a putative PD-specific composition of the gut microbiome, reflecting the potential relevance of microbiota in the pathogenesis of PD. Although methodologies and cohort sizes differed, the currently available studies showed reproducible or consistent results in terms of PD-specific alterations to the intestinal bacteria. By applying metagenomic sequencing procedures, it is even possible to distinguish PD cases from healthy individuals at a very early disease stage by means of individually modified microbiota. Among others, microbiota that are associated with an altered intestinal barrier or immune function, such as Akkermansia, Lactobacillus, Faecalibacterium and Prevotella were significantly over-represented or under-represented. There may even be a prodromal microbiome, as a comparable microbial shift is also found in patients with rapid eye movement (REM) sleep behavior disorder (RBD), a risk factor for the later development of synucleinopathies, such as PD.

The gut microbiome is associated with behavioural task in honey bees.

The gut microbiome is recognised as playing an integral role in the health and ecology of a wide variety of animal taxa. However, the relationship between social behavioural traits and the microbial community has received little attention. Honey bees are highly social and the workers perform different behavioural tasks in the colony that cause them to be exposed to different local environments. Here we examined whether the gut microbial community composition of worker honey bees is associated with the behavioural tasks they perform, and therefore also the local environment they are exposed to. We set up five observation hives, in which all workers were matched in age and observed the behaviour of marked bees in each colony over 4 days. The gut bacterial communities of bees seen performing predominantly foraging or predominantly in nest tasks were then characterised and compared based on amplicon sequencing of the 16S rRNA gene. Our results show that some core members of the unique honey bee gut bacterial community are represented in different relative abundances in bees performing different behavioural tasks. The differentially represented bacterial taxa include some thought to be important in carbohydrate metabolism and transport, and also linked to bee health. The results suggest an influence of task-related local environment exposure and diet on the honey bee gut microbial community and identify focal core taxa for further functional analyses.

[The rotationally stable screw-anchor with trochanteric stabilizing plate (RoSA/TSP) : First results in unstable trochanteric femur fractures]. / Der Rotationsstabile Schraubanker mit winkelstabiler Stützplatte (RoSA/TAP) : Erste klinische Evaluation bei instabilen trochantären Frakturen.

BACKGROUND: In unstable trochanteric fractures, the extramedullary rotationally stable screw-anchor (RoSA) combines the benefits of the load and rotational stability of the blade with the advantages of the screw (pull-out resistance, compression capability) in a single load carrier, and was designed to prevent femoral neck shortening by using an additional locked trochanteric stabilizing plate (TSP). OBJECTIVES: The aim of the current prospective cohort study was the clinical evaluation of the RoSA/TSP system regarding the mechanical re-operation rate and the amount of postoperative femoral neck shortening. METHODS: From September 2011 to January 2014 80 patients with unstable trochanteric fractures underwent internal extramedullary fixation with the RoSA/TSP (Königsee Implantate GmbH, Allendorf, Germany). Due to fracture stability and after induction of compression, additional long locked antitelescoping screws (AT, n = 1-4) were placed reaching the femoral head. Radiological (femoral neck shortening) and clinical re-examination of patients (n = 61) was performed 6-10 weeks and 6-10 months later. RESULTS: In the 61 re-examined patients (76 %) femoral neck shortening was very low with 2 mm 6-10 months after operation. Re-operations occurred in 8 % (n = 6) and in 4 % (n = 3) as prophylactic surgical intervention. Whereas one-third (4 %) of re-operations occurred due to iatrogenic surgical problems from the first operation two-thirds of patients (8 %) had a re-operation due to delay of bone union (3× nonunion, 3 planned removals of AT-screws to improve healing). The in-hospital mortality was 3 % (n = 2). CONCLUSIONS: The fixation of unstable trochanteric femur fractures using the RoSA/TSP in a first clinical setting led to a great primary stability, with significant advantages with regard to limited femoral neck shortening. However, the rigidity of the construct with its consequences regarding bone healing can be challenging for the surgeon. Nevertheless, in some cases of revision it could be beneficial for stability.

Sera from severe trauma patients with pneumonia and without infectious complications have differential effects on neutrophil biology.

BACKGROUND: Major trauma patients (TP) developing imbalanced immune response are at high risk for infectious post-injury complications including pneumonia. Neutrophils play a central role in the host defense against bacteria and thereby pathogenesis of infections. While there are numerous studies about neutrophil function after trauma, data about their biology in patients who suffer from pneumonia following trauma are sparse. Here, we studied the effect of serum isolated from patients who do and do not develop infection (inf.) on the biology of neutrophils from healthy volunteers. METHODS: Sera samples from eighteen TP with an injury severity score above 16 were obtained. Nine patients were grouped to no inf. group (TP without pneumonia), and nine to inf. group (TP with pneumonia). Samples were obtained at admission to emergency department (ED), a day prior pneumonia diagnosis (1 d prior inf) or at the day of diagnosis (1 d prior inf). Samples from the equal post-injury days in the corresponding no inf. group were used. Neutrophils from nine healthy volunteers were isolated. Effects for sera isolated from infected and non-infected patients on neutrophil biology were analyzed. Migratory capacity of neutrophils towards TP's serum, their CD11b and CD62L membrane receptor expression and oxidative burst activity after stimulation with TP's serum were determined and compared between groups. RESULTS: Migratory capacity of neutrophils was significantly increased after trauma and persisted during the study period. CD11b expression in all groups was significantly increased. CD62L expression decreased generally in samples from ED and recovered later to baseline. Stratifying no inf. and inf. groups showed significantly decreased migratory capacity, increased CD11b and significantly decreased CD62L expression in the no inf. group. These differences persisted during the complete observational period. ROS production was strongly reduced in the no inf. group compared to the inf. group at later experimental time points. CONCLUSIONS: This data indicate that patients at risk for pneumonia development have differentially and early activated neutrophils following trauma compared to patients who are not at risk for post-injury complication. Studies about the differential biology of neutrophils and their immediately after trauma modified activity depending on the post-injury clinical course are warranted, and may deliver predictive or even therapeutic strategies to control inflammation.

[Chronic instability of the pubic symphysis : Etiology, diagnostics and treatment management]. / Die Chronische Symphyseninstabilität : Ätiologie, Diagnostik und Behandlungsmanagement.

The most frequent causes of chronic instability of the pubic symphysis are sports-related continual overload and traumatic symphyseal injuries. Acute injury of the pubic symphysis may be the result of external forces acting on the anterior pelvic ring or the result of internal forces, such as those arising during parturition. The postpartum form of instability following a complication-free birth is reversible and usually returns to normal within a few months through strengthening of the pelvic floor muscles. Residual instability of the pubis symphysis is on the whole a rare complication. Although established therapy options for acute symphyseal separation can be found in the literature, there are only a few case reports on chronic symphyseal instability. There are no guidelines on standardized therapy options. This review article examines the etiology, clinical findings, diagnostic techniques and management options for patients suffering from chronic symphyseal instability.

[Diagnostics and treatment decisions in acute compartment syndrome. Results of a survey in German hospitals]. / Diagnostik und Therapieentscheidung beim akuten Kompartmentsyndrom. Ergebnisse einer Umfrage in deutschen Kliniken.

BACKGROUND AND OBJECTIVES: The presented survey was intended to evaluate whether a standardization of diagnostics and therapy for acute compartment syndrome has been achieved. MATERIALS AND METHODS: University hospitals, academic teaching hospitals, and county hospitals in Germany were included. RESULTS: A total of 38% (n=120) of all contacted hospitals participated in this study with questions mainly answered by consulting physicians (68%). In general the importance of the clinical examination was considered as being more important than other diagnostic measures. In cases where further diagnostics were necessary, the intramuscular pressure measurement was used most frequently. Of the participants 50% performed surgical fasciotomy based on the clinical examination in combination with the intramuscular pressure measurement; however, there were considerable differences between the participating hospitals with respect to the anatomical position of intramuscular measurements, the limiting value of the intramuscular pressure and the surgical technique for performing fasciotomy. CONCLUSION: According to the presented analysis the diagnosis and indications for surgical treatment in patients developing an acute compartment syndrome do not seem to be sufficiently clarified. The establishment of unified treatment guidelines could help to reduce the number of delayed diagnoses of compartment syndrome.

Local inflammation in fracture hematoma: results from a combined trauma model in pigs.

Background. Previous studies showed significant interaction between the local and systemic inflammatory response after severe trauma in small animal models. The purpose of this study was to establish a new combined trauma model in pigs to investigate fracture-associated local inflammation and gain information about the early inflammatory stages after polytrauma. Material and Methods. Combined trauma consisted of tibial fracture, lung contusion, liver laceration, and controlled hemorrhage. Animals were mechanically ventilated and under ICU-monitoring for 48 h. Blood and fracture hematoma samples were collected during the time course of the study. Local and systemic levels of serum cytokines and diverse alarmins were measured by ELISA kit. Results. A statistical significant difference in the systemic serum values of IL-6 and HMGB1 was observed when compared to the sham. Moreover, there was a statistical significant difference in the serum values of the fracture hematoma of IL-6, IL-8, IL-10, and HMGB1 when compared to the systemic inflammatory response. However a decrease of local proinflammatory concentrations was observed while anti-inflammatory mediators increased. Conclusion. Our data showed a time-dependent activation of the local and systemic inflammatory response. Indeed it is the first study focusing on the local and systemic inflammatory response to multiple-trauma in a large animal model.

Measurement of compartment elasticity using pressure related ultrasound: a method to identify patients with potential compartment syndrome.

PURPOSE OF THE STUDY Decision-making in treatment of an acute compartment syndrome is based on clinical assessment, supported by invasive monitoring. Thus, evolving compartment syndrome may require repeated pressure measurements. In suspected cases of potential compartment syndromes clinical assessment alone seems to be unreliable. The objective of this study was to investigate the feasibility of a non-invasive application estimating whole compartmental elasticity by ultrasound, which may improve accuracy of diagnostics. MATERIAL AND METHODS In an in-vitro model, using an artificial container simulating dimensions of the human anterior tibial compartment, intracompartmental pressures (p) were raised subsequently up to 80 mm Hg by infusion of saline solution. The compartmental depth (mm) in the cross-section view was measured before and after manual probe compression (100 mm Hg) upon the surface resulting in a linear compartmental displacement (Δd). This was repeated at rising compartmental pressures. The resulting displacements were related to the corresponding intra-compartmental pressures simulated in our model. A hypothesized relationship between pressures related compartmental displacement and the elasticity at elevated compartment pressures was investigated. RESULTS With rising compartmental pressures, a non-linear, reciprocal proportional relation between the displacement (mm) and the intra-compartmental pressure (mm Hg) occurred. The Pearson's coefficient showed a high correlation (r2 = -0.960). The intraobserver reliability value kappa resulted in a statistically high reliability (κ = 0.840). The inter-observer value indicated a fair reliability (κ = 0.640). CONCLUSIONS Our model reveals that a strong correlation between compartmental strain displacements assessed by ultrasound and the intra-compartmental pressure changes occurs. Further studies are required to prove whether this assessment is transferable to human muscle tissue. Determining the complete compartmental elasticity by ultrasound enhancement, this application may improve detection of early signs of potential compartment syndrome. Key words: compartment syndrome, intra-compartmental pressure, non-invasive diagnostic, elasticity measurement, elastography.

[Acute extremity compartment syndrome: current concepts in diagnostics and therapy]. / Das akute Kompartmentsyndrom der Extremitäten: Diagnostik und Behandlungsmanagement.

Acute compartment syndrome of the upper and lower limbs is observed following trauma, reperfusion or as an intraoperative complication caused by positioning. The pathophysiology of the disorder has been extensively described and is well known as a loss of perfusion due to rising compartmental pressures. It is a serious and potentially limb- and life-threatening complication. Early diagnosis is made primarily based on clinical findings. Early and focused therapy is crucial to prevent the devastating complications of this acute condition. However, diagnosis can be difficult, particularly in unconscious patients. Thus, in uncertain cases, pressure measurements are essential. Dermato-fasciotomy is the routine method to decompress the compartmental space. This review article examines the clinical findings, diagnostic techniques, and management options for the patient with musculoskeletal injuries.

[Biomarkers in pediatric polytrauma]. / Biomarker beim kindlichen Polytrauma.

BACKGROUND: Trauma represents one of the leading causes of death in children. Beside an injury pattern that differs from adult trauma patients, children seem to develop multiple organ dysfunction syndrome (MODS) less frequently. Compared to adult MODS, pediatric MODS has also been described to occur earlier in the posttraumatic course. METHOD: Biomarkers for early identification of patients at high-risk for posttraumatic complications are of high clinical relevance. However, little is known from clinical studies about the relevance of biomarkers during the posttraumatic course. AIM: Therefore, the purpose of this review is to summarize current knowledge on this topic in order to investigate the prognostic significance of different parameters.

Femoral shaft fractures in adults: treatment options and controversies.

Antegrade reamed femoral nailing via the piriformis entry point is the technique of choice in treating femoral shaft fractures, with retrograde nailing as an alternative. The supine position is favored to reduce complications, especially rotational malalignment. With navigation and robotic assistance fracture reduction can be supported and the rate of rotational, axis and length malalignement can potentially further reduced. Careful reaming is the procedure of choice to optimize bony healing and reduce systemic and local complications. In multiply injured patients reamed nailing can be safely integrated in the DCO- or ETC-concept and can be performed in the majority of patients, even when additional severe chest and head injuries are present. Initial resuscitation should focus on general stabilization before definitive femur fixation. Plate osteosynthesis of the femur can be an option in selected patients.

[Prognosis of polytraumatized patients: estimates in the shock room and intensive care station]. / Prognose des polytraumatisierten Patienten: Einschätzungen im Schockraum und auf der Intensivstation.

Treatment of patients with multiple trauma is known to require validated established algorithms, experienced medical staff and intensive interdisciplinary cooperation between the medical disciplines. In order to predict the risk for potential complications and mortality, adequate assessment of patients with multiple trauma is crucial for further treatment decisions. Therefore, different scoring systems have been developed to assess injury severity and to predict the potential outcome after multiple trauma. These scores have in common that the severity of trauma is converted to a numeric value simplifying the physiological reality in general. But the anatomic as well as physiological impact after multiple trauma can hardly be represented comprehensively by a single numeric value. Consequently, the established scores can only be safely interpreted, if the individual limitations of each scoring system are known.

Transverse + posterior wall fractures of the acetabulum: epidemiology, operative management and long-term results.

UNLABELLED: PURPOUSE OF THE STUDY: Associated transverse and posterior wall fractures account for approximately 20% of all acetabular fractures. To asses the risk of these concommitant bone injuries on early joint failure despite a high rate of postoperative congruency. MATERIAL: The analysis of 104 surgically treated patients with associated transverse and posterior wall fractures showed that more than half of these patients had associated injuries. The mean age was 35 years, and > 75% of these patients were male. A high energy trauma was the trauma mechanism in 94.2%. The mean ISS was 26.3 points. The majority of patients showed a juxta- or transtectal fracture line. The mean articular fracture displacement was 13.5 mm. 87.5% of the patients showed a femoral head dislocation. An acetabular roof comminution was present in 16.3%. 20.2% of patients received a fracture related preoperative nerve injury to the sciatic nerve. METHODS: Osteosynthesis was performed 9.9 days after trauma. The Kocher-Langenbeck approach was used in > 90% for stabilization with a combination of plate and screw fixation in 71.1%. The mean operative time was 190 minutes with a blood loss of 855 ml. Postoperatively the hip joint was congruent in 90.3% with anatomical or near-anatomical joint reconstruction in > 90%. Iatrogenic nerve injury occurred in 12 patients (8.9%). RESULTS: 67 patients (67.7%) could be followed after a mean of 42.7 months. The average subjective Visual Analog Scale pain score was 42.7. Mild or no pain was seen in 58.2%. The mean Merle d'Aubigné score was 15.4 with 56.7% of patients having a functionally perfect or good result. 52.2% had no post-traumatic osteoarthritic changes of their hip joint. A joint failure was diagnosed in 32.8% of the patients. Analyzing only patients with anatomically reconstructed hip joints, patients showed comparable results with 61.3% having no or mild pain and 59.2% a good or excellent functional result. Posttraumatic arthrotic changes occur in only 26.5% of these patients. A joint failure was present in 32.7%. In this group, a joint failure was significantly more likely to be present with an additional acetabular comminution zone. CONCLUSION: Associated transverse and posterior wall fractures have a significant risk of early joint failure despite a high rate of postoperative congruency.

Supraacetabular external fixation for pain control in geriatric type B pelvic injuries.

UNLABELLED: PURPOUSE OF THE STUDY: Pelvic ring fractures in the geriatric population are of increasing frequency. Often insufficiency fractures or occult fractures are described. With a classical injury mechanism the majority of these injuries are the result of a low energy trauma, typically a fall from standing or during walking.Clinically, many patients report immediate anterior groin pain but detailed clinical examination often shows significant posterior pelvic pain. CT evaluation often reveals posterior pelvic ring injury, in the majority of cases a sacral compression fracture. Despite adequate diagnostics, many of these patients suffer from persistent pain, which can be observed up to 8 weeks after injury. To asses the role of external fixator in pain relief and early mobilisation in this group of patients the study was performed. MATERIAL AND METHODS: From the database of all patients with pelvic ring and acetabular injuries 25 patients > 65 years with type B injuries stabilized by a supraacetabular external fixator were analyzed. Prospectively demographic data including sex, patient age, cause of injury, frequency and type of concomitant injuries and diseases, injury severity,fracture type and complications were recorded. For evaluation of the pain course, the visual analog scale was used. Preoperative and postoperative mobility and the type of post-treatment were evaluated. RESULTS: Stabilizing the pelvic ring with a simple external fixation procedure (supraacetabular one pin external fixator) allows immediate relief of pain, which allows early and successful mobilization of these patients. Normally, adequate mobilization is possible immediate after application of the fixator. CONCLUSIONS: This simple operative procedure, therefore, can be used for pain control and sufficient mobilization to avoid secondary medical complications.

Acetabular fractures in children: a review of the literature.

Injury to the acetabular growth plate is rare. Accordingly, data on the incidence in the literature are controverse. Other difficulties include the clear definition of a pediatric acetabular injury. The modified classification according to Salter-Harris described by Bucholz is used in immature patients. The majority of these injuries can be treated conservatively. In severely displaced injuries or in the presence of intra-articular pathologies open procedures are recommended. The main long-term complication is the development of posttraumatic acetabular dysplasia which should be early detected by regular check-ups until the completion of growth. Overall, the long-term results are satisfactory.

Non-invasive assessment of muscle compartment elasticity by pressure-related ultrasound in pediatric trauma: a prospective clinical study in 25 cases of forearm shaft fractures.

BACKGROUND: Soft-tissue swelling after limb fractures in pediatric patients is well known to be a risk factor for developing acute compartment syndrome (ACS). Clinical assessment alone is uncertain in specific cases. Recently, we proposed a non-invasive ultrasound-based method to objectify muscle compartment elasticity for monitoring. We hypothesize a strong correlation between the soft-tissue swelling after stabilization of upper limb fractures and the compartment elasticity objectified with a novel ultrasound-based approach in pediatric trauma. PATIENTS AND METHODS: In a prospective clinical study, children suffering forearm fractures but not developing an ACS were included. The muscle compartment elasticity of the m. flexor carpi ulnaris was assessed after surgical intervention by a non-invasive, ultrasound-based method resulting in a relative elasticity (RE in %) in both the control (healthy limb) and study group (fractured limb). Soft-tissue swelling was categorized in four different levels (0-3) and correlated with the resulting RE (%). RESULTS: The RE in the study group (15.67%, SD ± 3.06) showed a significantly decreased level (p < 0.001) compared with the control (22.77%, SD ± 5.4). The categorized grade of soft-tissue swelling resulted in a moderate correlation with the RE (rs = 0.474). CONCLUSIONS: The presented study appears to represent a novel approach to assess the posttraumatic pressure changes in a muscle compartment after fracture stabilization non-invasively. In this first clinical study in pediatric cases, our measurement method represents a low-cost, easy, and secure approach that has the potential to substitute invasive measurement of suspected ACS in muscle compartment conditions. Further investigations in lager cohorts are required to prove its daily clinical practicability and to confirm the expected reliability.