Outcome after total ankle replacement or ankle arthrodesis in end-stage ankle osteoarthritis on the basis of german-wide data: a retrospective comparative study over 10 years.

BACKGROUND: In symptomatic end-stage osteoarthritis of the ankle joint, total ankle replacement and ankle arthrodesis are the two primary surgical options for patients for whom conservative treatment fails. Published revision rates are often biased and difficult to compare. In this study, unplanned reoperation rates and revision rates were determined for both surgical interventions based on a large dataset, and risk factors for unplanned reoperations were identified. METHODS: German-wide health data of the largest German health-care insurance carrier between 2001 and 2012 were retrospectively analyzed, and unplanned reoperation rates within 10 years were determined for index surgeries conducted in 2001 and 2002. Unplanned reoperation rates within 5 years for index surgeries conducted in 2001/2002 were compared to index surgeries conducted in 2006/2007. Multivariate logistic regression was used to identify risk factors for unplanned reoperations. RESULTS: After ankle arthrodesis, 19% (95% confidence interval [CI], 16-22%) of 741 patients needed to undergo an unplanned reoperation within ten years. After total ankle replacement, the unplanned reoperation rate was 38% [95% CI, 29-48%] among 172 patients. For initial surgeries conducted at a later date, unplanned reoperation rates within five years were 21% [95% CI, 19-24%] for 1,168 ankle arthrodesis patients and 23% [95% CI, 19-28%] for 561 total ankle replacement patients. Significant risk factors for unplanned reoperations after ankle arthrodesis in the initial cohort were age < 50 years (odds ratio [OR] = 4.65 [95% CI 1.10;19.56]) and osteoporosis (OR = 3.72 [95% CI, 1.06;13.11]); after total ankle replacement, they were osteoporosis (OR = 2.96 [95% CI, 1.65;5.31]), Patient Clinical Complexity Level (PCCL) grade 3 (OR = 2.19 [95% CI, 1.19;4.03]), PCCL grade 4 (OR = 2.51 [95% CI, 1.22;5.17]) and diabetes mellitus (OR = 2.48 [95% CI, 1.33;4.66]). Kaplan-Meier analyses including 1,525 ankle arthrodesis patients and 644 total ankle replacement patients revealed an average unplanned reoperation-free time of approximately 17 years for both procedures. CONCLUSIONS: Similar revision rates and unplanned reoperation rates for both procedures in the later-date cohort can likely be attributed to a learning curve for surgeons as well as advances in implant design. This analysis of billing health insurance data supports an increase in total ankle replacement surgeries.

Net Promoter Score: a prospective, single-centre observational study assessing if a single question determined treatment success after primary or revision hip arthroplasty.

BACKGROUND: Our study aimed to identify the relationship between treatment outcome assessed by patient-reported outcomes (PROMs) and satisfaction measured by calculation of the Net Promoter Score (NPS), which identifies promoters, following total hip arthroplasty (THA). The aim was to evaluate this association separately in primary and revision THA and to determine thresholds based on PROMs that identify detractors of the surgical procedure or the centre. METHODS: A total of 1,243 patients who underwent primary or revision THA at our hospital were asked to complete questionnaires of the Oxford Hip Score (OHS), Euroquol-5D (EQ-5D) and information on pain intensity preoperatively, three and 12 months after surgery. Postoperatively, the patients were additionally asked about their satisfaction with the procedure and the hospital by using three different NPS questions. The association between PROMs and NPS was evaluated based on group comparisons of primary or revision THA and receiver operating characteristics analysis (ROC) to determine threshold values. RESULTS: At 12 months the NPS of all three questions were invariably linked to treatment outcome in patients after primary THA and patients with a single revision. In these two treatment groups, promoters always showed significantly better PROM scores than detractors. The NPS score was always higher in the primary group in comparison to the single revision group, e.g. 66.4% would undergo the procedure again in the first group, while only 33.0% would opt for this in the latter group. The high thresholds for the PROMs at 12 months, that were calculated by ROC analysis to identify promoter/detractors, indicate that patients` satisfaction required very good joint function and pain relief. However, the NPS was not a suitable tool to identify patients who need further care in an early phase after surgery. CONCLUSIONS: With NPS already a single question or a single parameter provides the desired information regarding patient satisfaction and also treatment success. TRIAL REGISTRATION: The study was approved by the Ethics Committee at the Medical Faculty of the University Rostock: "Ethikkommission an der Medizinischen Fakultät der Universität Rostock", Address: St.-Georg Str. 108 18055 Rostock, Germany, reference number: A2015-0055.

Intraoperative damage to surgical gloves during various operations on the musculoskeletal system: a multicenter study.

INTRODUCTION: Various orthopedic surgical procedures cause mechanical stress for gloves. In some cases, sharp-edged objects impact on the glove surfaces. The systematic description of lesions is still missing. METHODS: 2289 gloves from 409 surgeries [primary hip and knee arthroplasties (PA), revisions arthroplasties (RA) and arthroscopic shoulder, hip and knee surgery (AY)] from 3 clinics were examined for lesions using water tightening test according to the European norm EN 455-1. RESULTS: Arthroscopies showed the lowest rate of operations with damaged gloves (6.9%). Depending on clinic, 32.7% and 59.2% of PA surgeries generated damaged gloves, while in RA, these numbers rose to 76.0% and 72.8%, respectively. In PA and RA, the most affected finger was the index finger, whereas in arthroscopies, more damage occurred on the middle finger and the thumb. The size of the lesions was rather small with the vast majority being 1 mm or 2 mm in size. CONCLUSION: All investigated interventions led to glove lesions. With increasing mechanical stress, the number of glove defects increased. EN 455 does not account for the intraoperative tear risk. Stricter requirements for gloves should be introduced. Glove change intervals should be defined and implemented, and new materials should be developed.

Evaluation of the standard procedure for treatment of periprosthetic joint infections of total knee and hip arthroplasty: a comparison of the 2015 and 2020 census in total joint replacement centres in Germany.

BACKGROUND: There are different procedures for both, the diagnosis and the therapy of a periprosthetic joint infection (PJI), however, national or international guidelines for a standardised treatment regime are still lacking. The present paper evaluates the use of the predominant treatment protocols for PJI in certified total joint replacement centres (EPZ) in Germany based on an EndoCert questionnaire. MATERIALS AND METHODS: The questionnaire was developed in cooperation with the EndoCert Certification Commission to survey the treatment protocols for septic revision arthroplasties in EPZ. Questions targeted the various treatment options including prosthesis preserving procedures (DAIR - Debridement, antibiotics, irrigation, and retention of the prosthesis), one-stage revision, two-stage revision, removal of the endoprosthesis and diagnostic sampling prior to re-implantation. All certified EPZ participated (n = 504) and the results from the current survey in 2020 were compared to data from a previous analysis in 2015. RESULTS: The number of centres that performed DAIR up to a maximum of 4 weeks and more than 10 weeks after index surgery decreased since 2015, while the number of centres that provided a one-stage revision as a treatment option increased (hip: + 6.3%; knee: + 6.6%). The majority of the centres (73.2%) indicated a 4-8 week period as the preferred interval between prosthesis removal and re-implantation in two-stage revision in hip as well as knee revisions. Centres with a higher number of revision surgeries (> 200 revisions/year), opted even more often for the 4-8 week period (92.3%). In two-stage revision the use of metal-based spacers with/without reinforcement with antibiotic-containing cement as an interim placeholder was significantly reduced in 2020 compared to 2015. There was also a clear preference for cemented anchoring in two-stage revision arthroplasty in the knee in 2020, whereas the majority of hip replacements was cementless. Additionally, in 2020 the number of samples for microbiological testing during the removal of the infected endoprosthesis increased and 72% of the centres took five or more samples. Overall, the number of EPZ with a standardised protocol for the procedure expanded from 2015 to 2020. CONCLUSION: While there was a trend towards standardised therapeutic algorithms for PJI with more uniform choices among the centres in 2020 compared to 2015, the treatment often remains an individual decision. However, since a consistent treatment regime is of vital importance with an expected rise of total numbers of revision arthroplasties, uniform definitions with regard to comparability and standardisation are necessary for the further development of the EndoCert system.

[Readmission rates of back pain patients after primarily conservative inpatient treatment at a university hospital]. / Wiederaufnahmeraten von Rückenschmerzpatienten an einer Universitätsklinik nach primär konservativer stationärer Therapie.

BACKGROUND: The number of patients receiving inpatient treatment for back pain is increasing, as the current structures of outpatient care cannot meet the demand adequately. Although the infrastructure of the maximum care provider ensures possible emergency care and imaging procedures on the one hand, it is not geared to providing replacement services for outpatient care on the other. OBJECTIVES: Analysis of the readmission rates of primarily conservatively treated inpatients with back pain. MATERIALS AND METHODS: In this retrospective study, the recovery rate of patients with back pain who were admitted as emergency inpatients and treated primarily conservatively as inpatients was investigated within 6 months at a university orthopaedic clinic. The study period was 2 years with a follow-up of 6 months. 413 patients were evaluated. RESULTS: After primarily conservative therapy, 17.9% of the patients were readmitted to hospital. It took 25 (±33.25) days until the first readmission and 25.9 (±31.99) days until the second readmission. Pensioners were admitted to hospital significantly more often but were treated mainly conservatively during their stays; 66.8% of the presentations were emergencies without referral. CONCLUSIONS: Readmission after primarily conservative inpatient treatment is relatively high. In most cases, the return of the patient to outpatient care can be achieved by tight management with a rapid diagnostic procedure and targeted aftercare strategies. The patient may return to outpatient care for surgical treatment or, unplanned, due to failed conservative, outpatient treatment.

Evaluation of the standard procedure for the treatment of periprosthetic joint infections (PJI) in Germany - results of a survey within the EndoCert initiative.

BACKGROUND: The periprosthetic joint infection (PJI) is a severe complication in the field of arthroplasty. Despite the rising number of primary joint replacements, no unified therapeutic standard has been established for the treatment of PJI yet. METHODS: A survey on the principles of treatment of PJI in Germany was conducted. A total of 515 EndoProthetikZentren (EPZ) were included, resulting in a response rate of 100%. RESULTS: For early infections 97.6% of the centers use prosthesis-preserving procedures (DAIR). A one-stage exchange was implemented by less than 50% of the centers. If implemented, this treatment entails a prior selection of patients for a successful treatment. The two-stage exchange is performed in all centers, and most centers proceed with the implantation of a cemented spacer between stages. 75% of the centers proceed with a center-based concept for the treatment of PJI. CONCLUSION: The aim of a uniform PJI standard at the centers has not yet been fully achieved. Further improvements within the certification were initiated. The most relevant treatment options in Germany are displayed. The two-stage revision with a cemented spacer is the most widely implemented treatment. This exposition of principles could help for the further development of standardized treatment guidelines and definitions.

[Medical device training in arthroplasty : National practice and quality standards]. / Medizinprodukteschulungen in der Endoprothetik : Nationale Praxis und Qualitätsansprüche.

The qualified training of users of medicinal products is enshrined in law by the Medical Devices Act. In this article, a survey and analysis of the training measures for arthroplasty of the large joints offered by distributors of medical devices is carried out. To that end, the internet presence of suppliers of medical devices was evaluated with regard to the training measures on offer, and selected suppliers were sent questionnaires. The presentation of the available training programmes on the websites was incomplete. Even after the amendment of the Medical Devices Act, this has only slightly changed; however, legally required instructions for use were available for all distributors questioned. In some cases, there are large gaps in the range of modern training methods on offer, such as practical instruction, multimedia offerings or visual-haptic training methods.

Institutional Surgical Setting and Volume Effects of Certified Arthroplasty Centers in Germany: Evaluation of the Quality of Care in a 5-Year Comparison.

To improve arthroplasty care quality, the EndoCert initiative focuses on structural, processual, and surgeon-related quality assurance. The aim of this study was to assess the impact of a surgeon's case load in certified centers on quality of care, distinguished by different types of surgeons. Data from the annual reports of EndoCert certified centers for the years 2017 to 2021 were analyzed. The study revealed reduced numbers of cases, while the number of surgeons remained constant. Since 2020, the decrease in the average case load per surgeons has become more pronounced. There were also differences between senior (sECrs) and EndoCert-registered surgeons (ECrs). Before the 2020 pandemic, over half of surgeons exceeded minimum annual case requirements, while, afterwards, this number declined, especially for the ECrs. Affiliated surgeons, who are also sECrs or ECrs, performed predominantly lower numbers of arthroplasties. However, a higher percentage of affiliated surgeons in a center correlated with faster surgeries and lower mortality rates. High numbers of arthroplasties per center or surgeon were not necessarily associated with better quality indicators, especially in the knee. While the comprehensive quality standards may offset volume effects, EndoCert should reconsider minimum volume regulations based on surgeon, but also on each joint.

Identification of Potentially High-risk Patients on the Basis of PROMs in a Certified Centre for Joint Replacement (EndoProthetikZentrum) Using the Example of Primary Knee Arthroplasty. / Identifikation von potenziellen Risikopatienten auf Basis von PROMs in einem zertifizierten EndoProthetikZentrum am Beispiel der primären Knieendoprothetik.

BACKGROUND: The subjective evaluation of the patient's state of health with the help of Patient-reported Outcome Measurements (PROMs) provides valuable information for assessing the treatment outcome and for treatment planning. However, the use of PROMs in the field of arthroplasty is not mandatory, so that there is a lack of standardised recording and interpretation. The present study aims to identify patients, who have not achieved the intended treatment goals with regard to pain, function and quality of life after total knee arthroplasty, more easily in the future on the basis of postoperative PROMs. MATERIAL AND METHODS: Data collection (for 3-month postoperative follow-up) included a standardised clinical follow-up (NU) and a questionnaire of different PROMs (Oxford Knee Score [OKS], OKS Pain Score [OKSS] and EndoCert Risk Score [ERS]). During the specialist follow-up examination, it was decided whether further medical therapy had to be initiated. Accordingly, patients were grouped into four post-treatment categories (NU not required/further diagnostics/new prescription/revision required). RESULTS: For individual scores and questions, there were significant differences between the respective groups of consequences resulting from the follow-up examination. The OKS, OKS Pain Score and the ERS are suitable for detecting thresholds to determine the need for a follow-up examination. The postoperative thresholds of the scores are 24 for the OKS total score, 52 for the OKS pain score and 4 for the ERS pain intensity score. CONCLUSION: In the initial three months after knee arthroplasty, certain PROMs are suitable for identifying patients for whom further diagnostics and therapy are indicated. In particular, the OKS and the pain intensity score of the ERS are suitable for detecting a potentially unfavourable development in rehabilitation after total knee arthroplasty.

[Three-year revision rate of certified centres for joint replacement according to EndoCert : Risk-adjusted analysis of outcome quality and comparison with other quality assurance systems]. / 3-Jahres-Revisionsrate von zertifizierten EndoProthetikZentren nach EndoCert : Risikoadjustierte Analyse der Ergebnisqualität und Vergleich mit anderen Qualitätssicherungssystemen.

BACKGROUND: The EndoCert initiative does not yet allow a long-term assessment of outcome quality. The assessment cannot be achieved without cooperation with the German arthroplasty registry (EPRD) and other quality assurance infrastructure, such as the quality assurance system of the nationwide healthcare insurance data for inpatient hospital treatment (QSR) by the German local healthcare fund (AOK). Therefore, the quality of care of all certified centres for joint replacement (EPZ) after primary hip and knee arthroplasty was to be examined for the first time. These data were subsequently compared to the data of the EPRD. MATERIALS AND METHODS: In EPZ that provided care to at least one AOK-insured patient in 2016, the risk-adjusted 3­year revision rate and the SMR-value (standardised mortality or morbidity ratio), which is the quotient of the observed and expected revision rate, were analysed as markers for the quality of care. Annual hospital volume, type of centre and audit results were examined as possible influencing factors. RESULTS: In the group comparison, significant differences (p = 0.042) for the SMR value of the 3­year revision rate were demonstrated for hip arthroplasty with regard to the EPZ type. The annual number of primary hip arthroplasties, however, did not influence the 3­year revision rate. For knee arthroplasties, no effect of the defined categories on the 3­year revision rate and its SMR value was observed. The comparison of our 3­year revision rates with those of the EPRD showed similar results for the hip but indicated significant differences for the knee. CONCLUSION: We did not observe a correlation between quality of care and annual hospital volume in certified EPZ. However, different quality assurance procedures can lead to different results with respect to the outcome quality. Therefore, a considerably improved interaction of the German quality systems must be achieved. Participation in the EPRD is not sufficient for this. Rather, a complete report of all arthroplasties must be required, at least with the achievement of a minimum reporting rate per participating hospital. Uniform inclusion and exclusion criteria should be defined.

Surgical Treatment of Adolescent Idiopathic Scoliosis with the ApiFix Minimal Invasive Dynamic Correction System-A Preliminary Report of a 24-Month Follow-Up.

Adolescent idiopathic scoliosis (AIS) is a three-dimensional growth disorder. Corrective surgical procedures are the recommended treatment option for a thoracic angle exceeding 50° and a lumbar major curve of 40°. Over the past few years, dynamic growth modulation implants have been developed as alternatives to permanent fusion. The ApiFix system was designed as a 2D "posterior dynamic device" for curve correction. After implantation in a minimally invasive procedure, it uses polyaxial joints and a self-adjusting rod to preserve the degree of motion and to accommodate the patient's growth. It provides an effective method of controlling deformity and fills the gap between the conservative treatment of major curves that are >35° and the fusion procedure. The objective of the two-center cohort study was the analysis of the correction results of patients, who underwent surgical intervention with the ApiFix system. The inclusion criteria were AIS, Lenke type 1 or type 5, a major curve on bending films of ≤30°, and an angle of the major curve of between 35° and 60°. Postoperative radiograph data were obtained longitudinally for up to 24 months of follow-up and compared to preoperative (preop) values. For comparisons of the different time points, non-parametric tests (Wilcoxon) or paired t-tests for normally distributed values were used to analyze repeated measures. Overall, 36 patients (25 female and 11 male) were treated with the ApiFix system from April 2018 to October 2020. Lenke type 1 was identified in 21 (58%) cases and Lenke type 5 was identified in 15 (42%) cases. The average angle of the thoracic major curve for Lenke 1 was 43°. The preoperative lumbar major curve (Lenke 5) was determined to be 43°. Over a follow-up of 24 months, a correction of the major curve to an average of 20° was observed for Lenke 1 and that to an average of 15° was observed for Lenke 5. Lenke type 1 and type 5 showed significant changes in the major curve over the individual test intervals in the paired comparisons compared to the starting angle (Lenke 1: preop-24 months, 0.002; Lenke 5: preop-24 months, 0.043). Overall, 11 events were recorded in the follow-up period, that required revision surgery. We distinguished between repeated interventions required after reaching the maximum distraction length of the implant due to the continued growth of the patient (n = 4) and complications, such as infections or problems associated with the anchorage of the implant (n = 7). The results from the present cohort revealed a statistically significant improvement in the postoperatively measured angles of the major and minor curves in the follow-up after 24 months. Consequently, the results were comparable to those of the already established vertebral body tethering method. Alignment in AIS via dynamic correction systems in combination with a possible growth modulation has been a treatment alternative to surgical fusing procedures for more than a decade. However, the long-term corrective effect has to be validated in further studies.

[Planning revision hip arthroplasty : What are the structural requirements?] / Planung des Hüftendoprothesenwechsels : Welche strukturellen Voraussetzungen müssen gegeben sein?

The results of many studies and register reports show that the frequency of primary hip arthroplasty per hospital, but also per surgeon, influence the outcome. In the large spectrum of revision hip arthroplasty volume-outcome effects have also partially been proven. It is obvious that with the increasing complexity of revision surgery and comorbidities, higher demands exist concerning collaborating disciplines as well as training and intervention frequency of the surgical team. Further aspects regarding organisation and structure such as the availability of specific revision implants and instruments must be ensured. In order to provide sustainable resources for revision surgery in an arthroplasty centre, organization of education and training for staff members in different disciplines and working levels must be ensured without quality impairment.

[Comparative study of postural control in 20-40 years olds and karate athletes using a neuromuscular training device]. / Vergleichende Untersuchung der posturalen Kontrolle bei 20­40-Jährigen und Karate-Kaderathleten mittels eines neuromuskulären Trainingsgerätes.

BACKGROUND: Postural control helps maintain upright posture and contributes to balance regulation. Increasing neuromuscular deficits in older subjects lead to a deterioration in postural control, which can be improved through neuromuscular training. Assuming that neuromuscular deficits occur at an early age, the postural abilities of 20 to 40 year olds were investigated. In addition, the influence of competitive sports on postural control was examined by including karate squad athletes. METHODS AND MATERIAL: For an age comparison, 123 age-homogeneous healthy people between 20 and 40 years were examined. 24 karate squad athletes were compared with the 20 -25 year old healthy subjects. A neuromuscular training device, the Human Body Equilibrium 360, was used to collect data. RESULTS: In the age comparison, there were no significant differences for all seven measurements. The study group was too young to detect deficits. However, some general findings could be published. In the two-legged stance, a significant increase in the fluctuations of the body centre of gravity after eye closure could be seen in all groups. The influence of footedness and handedness could be seen in the one-legged stance and the strength test. Gender-specific differences could be observed. The examination of karate squad athletes showed various training-specific adaptations. For example, karate athletes were better able to compensate for the loss of visual information. Karate athletes also showed a significantly wider gait pattern and a larger stability area. Athletes were able to shift their body centre of gravity further without getting out of balance. CONCLUSION: The Huber 360 is only conditionally suitable as a rehabilitation and training device, due to the low discriminatory power of the tests in its entire range of applications, as significant differences between the groups are difficult to detect. Individual training specific adaptations through performance-oriented karate training are recognisable and underline the influence of training on postural control. In summary, the use of the Huber 360 to assess postural abilities in age comparisons and to distinguish training specific adaptations requires a differentiated and more selective use of the individual tests. Further studies with older patients with different diseases are planned.

Identification of Potential High-Risk Patients on the Basis of PROMs in a Certified Centre for Joint Replacement (EndoProthetikZentrum) Using the Example of Hip Arthroplasty. / Identifikation von potenziellen Risikopatienten auf Basis von PROMs in einem zertifizierten EndoProthetikZentrum am Beispiel der Hüftendoprothetik.

BACKGROUND: In addition to clinical parameters, the subjective assessment by the patient to evaluate the operative outcome of an arthroplasty is becoming increasingly important. Questionnaires are used to identify patients who have not achieved the treatment goal at an early stage so that further interventions can be indicated. MATERIAL AND METHODS: A questionnaire consisting of different PROMs was completed pre- and 3 months postoperatively by patients who had been treated with a hip arthroplasty. A standardised follow-up examination of these patients was carried out 12 to 16 weeks postoperatively, after which it was determined whether further therapy was necessary to achieve the treatment goal. Different consequences were defined for this. RESULTS: Significant differences were found between the groups of consequences of follow-up examinations over both time points, but also when postoperative scores were considered exclusively. Furthermore, the correlations for the postoperative scores and some consequences of the clinical follow-up for the Oxford Hip Score (OHS), the OHS functional score and the Euroquol-5D show moderate effects. Thus, the collection of these postoperative scores is sufficient to identify potential high risk patients. Based on a receiver operating characteristic (ROC) analysis, threshold values could be determined for these scores, for which a follow-up examination is recommended. CONCLUSION: Patients who could not achieve functional improvement, pain reduction and improvement in quality of life after implantation of a total hip replacement must be identified at an early stage. The results of our study show that with the help of the Oxford Hip Score and Euroquol-5D, which are answered by the patients three months postoperatively, such high risk patients can be identified. This finding is an added value for the further development of the EndoCert certification system and holistic quality assurance in arthroplasties, while the personnel and time effort remain manageable.

The effect of the design of the orthosis on the axial load transmission of two flexion abduction orthoses used in treating congenital hip dysplasia.

Background: With an incidence of 2-4% in all newborns, developmental dysplasia of the hip, DDH, represents the most frequent congenital disorder of the skeletal system in Germany. The therapy options are deduced with the help of a sonography. The conservative therapy approach includes the application of flexion abduction orthoses, which lead to a development of the child's hip through abduction and flexion angle. The overall structure of the orthoses puts a strain on the axial skeleton of the children. The following work is intended to clarify what role the design of the orthoses plays in this respect. Methods: Inclusion criterion for the study was fully developed newborns without an indication of skeletal malformations with Type I hip joints according to Graf verified by ultrasound. A total of 19 newborns were recruited and included in the period 3/2013-01/2015. Two types of orthoses used in treating developmental dysplasia of the hip (Tübinger splint, Otto Bock; hip flexion abduction orthosis (Superior orthosis) according to Mittelmeier-Graf, AIDAMED e.K (Kreuz et al., 2012; Mittelmeier et al., 1998; Schmitz et al., 1999), constructions differ, were used. Force was measured with the help of three force sensors, which were even able to be integrated into these without changing the design of the orthosis. In this closed system, force transmission was measured for the duration of a fixed period of two minutes. Findings: The greatest axial force development (overall force) is in the Tübinger splint with an average force of 15.1 N (min. 0.59 N, max. 53.09 N, mean 15.1, SD 2.46). 4.09 N (min. 0.96 N, max. 20.99 N, mean 4.09, SD 0.65) resulted in the Superior orthosis. Significant correlations between body weight and resulting axial traction - on average during the entire measurement period and in movement - can be taken from the statistical analysis regarding the Tübinger splint. Such a correlation cannot be depicted for the Superior orthosis. Interpretation: The analysis of the load transmission of the examined flexion and abduction orthoses reveals differences between the models. The construct of the orthoses in itself appears to play a significant role. Long-term effects of orthosis therapy on a child's axial skeleton have not been studied to date. Furthermore, it seems reasonable to expand the test series to orthoses, the design of which is configured in a similar matter compared to the examined aids. Conclusion: This study proves that the orthotic design has an influence on the infant's axial load.

Influence of Revision Surgeries and Revision Rate on Quality Indicators in Certified Centres for Joint Replacement (EndoProthetikZentren). / Einfluss der Wechseleingriffe und der Wechselrate auf die Qualitätsindikatoren in zertifizierten EndoProthetikZentren.

BACKGROUND: The annual report of EndoCert publishes the results of the quality indicators (QI) and key figures of all certified centres for joint replacement (EndoProthetikZentren - EPZ). For some results it seems that centres with fewer revisions might have higher complication rates. However, to avoid misinterpretation the results have to be evaluated in more detail. The influence of the quantity of the revisions or the revision quotient on the quality of outcome was investigated. MATERIAL AND METHODS: This study included all certified EPZ and centres of excellence for joint replacement (EPXmax) (n = 492) and evaluated the data from 2016. Centres beyond the action limit were identified with the help of funnel plots and a confidence limit of 99.7% as action limit. Additionally data of the quality indicators were analysed with ANCOVA. The level of significance was p < 0.05. RESULTS: The comparison by ANCOVA with number of revisions as co-variate showed no differences in the complication rates when related to the quantity of revisions. When considering a so called revision quotient (ratio of revision to all joint replacements) significant differences in the rate of fractures and fissures as well as in mortality for hip replacements and also in mortality for knee replacements were observed. CONCLUSION: EPZ with fewer revisions do not have higher complication rates than centers with high numbers of revisions. Thus, the quantity of revisions has no influence on the quality of the outcome, considering that on the basis of the data of the EndoCert system no risk adjustment of patient-specific data was performed. Therefore the revisioin quotient of an EPZ shows that quantity is not equal with quality.

A Proof of Concept Study Regarding the Utilization of Different Patient-related Outcome Measurements in a Certified Centre of Excellence for Joint Replacement (EndoProthetikZentrum). / Machbarkeitsstudie zum Einsatz verschiedener Patient-related Outcome Measurements in einem zertifizierten EndoProthetikZentrum.

BACKGROUND: The aim of the study is to identify those patients without improved pain sensation and functionality of the joint, thus with a potential necessity of re-intervention by using the evaluation of the PROMs (Oxford Hip Score, European Quality of Life Scale, EndoCert-Risk-Score). The task was to determine the value of the scores which represents the limit above/below, which a re-examination of the patient is necessary. Additionally, further secondary objectives such as influence of complications on scores, the percentage of questionnaire return and the quality of the provided data in the questionnaires were recorded to define minimal requirements on patient's response. MATERIAL AND METHODS: Members of the EndoCert certification committee developed a questionnaire for pre- (decision on treatment) and post-operative (discharge and 3-months follow-up) use. A total of 112 primary hip replacements and 25 hip revision arthroplasties, which were recruited from a centre of excellence for joint replacement (EndoProthetikZentrum der Maximalversorgung), were included in the study. RESULTS: The return of questionnaires amounted to 80%. Quality of data in the questionnaires declined with BMI (≥ 25), ASA classification (≥ 3), age (≥ 65) and depended on the time point questioning. Based on the EndoCert risk score there was a significant improvement in the experience of pain postoperatively compared to pre-operation (p < 0.05). However, the functionality of the joint, as measured as the use of walking frames or crutches as well as the need for help from others, did not improve. The results revealed that there was no correlation between the incidence of complications and a detrimental score. It was furthermore shown that patient specific attributes, e.g. age or BMI, or perioperative performance (duration of operation) did not influence the likelihood of a complication. CONCLUSION: It was shown that Oxford Hip Score and EQ-5D were not negatively influenced by complication during hospital stay. The evaluation of the EndoCert risk score showed not improvement between pre- and post-operative values regarding function but revealed a significant pain relief. A further study is intended to evaluate the intensity of pain after three months as part of an extended systemic follow-up. This could provide further insights whether the EndoCert risk score is a suitable tool to identify unsuccessfully treated patients.

Influence of Training of Orthopaedic Surgeons on Clinical Outcome after Total Hip Arthroplasty in a High Volume Endoprosthetic Centre. / Einfluss des sich in Weiterbildung befindlichen Operateurs auf die postoperative Ergebnisqualität nach hüftendoprothetischer Versorgung in einem EndoProthetikZentrum der Maximalversorgung.

BACKGROUND: The study aims to evaluate whether the postoperative outcome and the probability of complications of patients with total hip arthroplasty increases significantly when surgeons in training are in charge, assisted by a high volume surgeon, compared to a highly experienced orthopaedic surgeon, within the context of a high volume hospital certified to EndoCert. MATERIAL AND METHODS: 192 patients with a primary hip arthroplasty were included. To assess the outcome, the Harris Hip Score, WOMAC, SF-36 and EuroQol-5D were surveyed pre- and 12 months postoperatively. As complications we considered the quality indicators defined by EndoCert. RESULTS: We found significant improvements in the postoperative score values with the qualifications of the surgeon in charge, even when a high volume surgeon or a surgeon in training was responsible. If a surgeon in training is assisted by a highly experienced surgeon, the risk of complications does not increase, although the operating time was significantly increased. CONCLUSION: Both the surgeon in training as well as the arthroplasty patient benefit from implementing the EndoCert system, because the postoperative outcome and the complication probability is independent of the qualifcation of the operating orthopaedic surgeon performing total hip arthroplasty when assisted by an experienced surgeon.