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.

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.

The influence of surgical technique guidance and surgeon's experience on the femoral head assembly in total hip arthroplasty.

INTRODUCTION: The importance of the assembly procedure on the taper connection strength is evident. However, existent surgical technique guides frequently lack comprehensive and precise instructions in this regard. The aim of our experimental study was to evaluate the influence of the surgical technique guide on the femoral head assembly procedure in surgeons with differing levels of experience in total hip arthroplasty. MATERIALS AND METHODS: Twenty-eight participants, divided into four groups based on their lifetime experience in total hip arthroplasty, conducted a femoral head assembly procedure in a simulated intraoperative environment before and after reviewing the surgical technique guide. Demographic information and the number of hammer blows were documented. Hammer velocity and impaction angle were recorded using an optical motion capturing system, while the impaction force was measured using a dynamic force sensor within the impactor. RESULTS: We observed a high variation in the number of hammer blows, maximum force, and impaction angle. Overall, the number of hammer blows decreased significantly from 3 to 2.2 after reviewing the surgical technique guide. The only significant intragroup difference in the number of hammer blows was observed in the group with no prior experience in total hip arthroplasty. No correlation was found between individual factors (age, weight, height) or experience and the measured parameters (velocity, maximum force and angle). CONCLUSIONS: The present study demonstrated a high variation in the parameters of the femoral head assembly procedure. Consideration of the surgical technique guide was found to be a limited factor among participants with varying levels of experience in total hip arthroplasty. These findings underline the importance of sufficient preoperative training, to standardize the assembly procedure, including impaction force, angle, and use of instruments.

Vitamin E-enriched medium cross-linked polyethylene in total knee arthroplasty (VIKEP): clinical outcome, oxidation profile, and wear analysis in comparison to standard polyethylene-study protocol for a randomized controlled trial.

BACKGROUND: The gliding surface of total knee endoprostheses is exposed to high loads due to patient weight and activity. These implant components are typically manufactured from ultra-high molecular weight polyethylene (UHMWPE). Crosslinking of UHMWPE by ionizing radiation results in higher wear resistance but induces the formation of free radicals which impair mechanical properties after contact with oxygen. Medium-crosslinked UHMWPE enriched with vitamin E (MXE) provides a balance between the parameters for a sustainable gliding surface, i.e., mechanical strength, wear resistance, particle size, and oxidation stability. Therefore, a gliding surface for knee endoprostheses made up from this material was developed, certified, and launched. The aim of this study is to compare this new gliding surface to the established predecessor in a non-inferiority design. METHODS: This multicenter, binational randomized controlled trial will enroll patients with knee osteoarthritis eligible for knee arthroplasty with the index device. Patients will be treated with a knee endoprosthesis with either MXE or a standard gliding surface. Patients will be blinded regarding their treatment. After implantation of the devices, patients will be followed up for 10 years. Besides clinical and patient-related outcomes, radiological data will be collected. In case of revision, the gliding surface will be analyzed biomechanically and regarding the oxidative profile. DISCUSSION: The comparison between MXE and the standard gliding surface in this study will provide clinical data to confirm preceding biomechanical results in vivo. It is assumed that material-related differences will be identified, i.e., that the new material will be less sensitive to wear and creep. This may become obvious in biomechanical analyses of retrieved implants from revised patients and in radiologic analyses. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04618016. Registered 27 October 2020, https://clinicaltrials.gov/study/NCT04618016?term=vikep&checkSpell=false&rank=1 . All items from the World Health Organization Trial Registration Data Set can be found in Additional file 1.

Comparison of the Influence of Supportive and Sensorimotor Insoles on Flat Feet in Children - a Double-Blind, Prospective, Randomized, Controlled Trial.

BACKGROUND: Besides arch-supportive insoles, sensorimotor insoles are used for the treatment of flatfoot in children. The aim of this study was to compare the effect of both types of insoles on the arch-supporting muscles and clinical aspects in children with flexible flatfoot. MATERIAL AND METHODS: 52 children with flexible flatfoot (mean age of 8.22.7 years) were enrolled. Supportive, sensorimotor, and placebo insoles were compared. Muscle activity was detected by surface electromyography during the midstance phase. Valgus index, foot and ankle disability index (FADI) and pain were assessed at enrolment and after 6 and 12 months. Mixed-design ANOVA was used for statistical evaluation. RESULTS: Supportive and sensorimotor insoles caused significantly lower activity in the tibialis anterior in comparison to placebo insoles regarding the parameter Mean. No significant differences could be detected between both types of therapeutic insoles. Supportive insoles showed a significant decrease regarding the parameter Amplitude of the peroneus longus. Placebo insoles produced an increase in the valgus index, while both therapeutic insoles did not induce any changes. The sensorimotor insoles induced an increase in FADI, while the supportive and placebo insoles had no significant effect on this parameter. CONCLUSIONS: 1. Supportive and sensorimotor insoles potentially influence muscle activity in the lower leg. 2. Both could influence the longitudinal arch in flat feet. 3. While placebo insoles caused a deterioration of the valgus index, both kinds of therapeutic insoles could possibly prevent the progression of the flatfoot. 4. Clinical studies including more clinical aspects and long-term observations are necessary.

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.

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.

Stability of ceramic coatings on retrieved knee prostheses.

BACKGROUND: In total knee arthroplasty, femoral components with coated or oxidized surfaces are commonly used as alternative to CoCrMo in metal sensitive patients. Data on the in vivo behaviour of different coating types is, however, rare. Aim of the study was the investigation of coating stability with respect to implant and patient specific parameters. METHODS: Coating thickness and coating thickness reduction, respectively, was measured at 37 retrieved femoral components with TiNbN, TiN, ZrN or oxidized zirconium (OxZr) surface by the crater grinding method. The results were correlated to surface type, manufacturer, time in vivo of the implant, patient body weight and patient activity. RESULTS: Mean coating thickness reduction in the overall retrieval collection was 0.6 µm ± 0.8 µm. There was no correlation between coating thickness reduction and coating type, time in vivo, patient body weight, and patient activity. If grouped according to manufacturers, implants of one manufacturer showed an increased coating thickness reduction. 10 of 37 retrievals exhibited coating abrasion with exposure of the underlying alloy. TiNbN coatings showed the highest incidence (9/17) of coating abrasion. No coating breakthrough was observed in the ZrN or OxZr surfaces. CONCLUSION: Our results indicate that TiNbN coatings should be optimized to improve their wear resistance in the long-term.

Constrained metal-on-metal hip arthroplasty: ever heard of a 50-year survival story?

BACKGROUND: The history of total hip arthroplasty dates back to the first half of the twentieth century. Data on hip endoprostheses implanted during the 1960s and 1970s suggest widely varying survival rates of the prosthesis. CASE: A case of a patient who underwent total hip arthroplasty in 1972 using a Sivash prosthesis, developed in 1956 in the former Soviet Union, is presented in this article. The prosthesis has remained unrevised in the patient's body for 50 years and he continues to be widely free of implant-related symptoms. Despite the constrained metal-on-metal design of the implant, which can lead to adverse reactions to metal debris, no elevated systemic metal ion levels were detected. CONCLUSION: The likelihood of encountering patients with prosthesis survival beyond 50 years is still rare. Nevertheless, changing demographics and the steadily improving designs and materials of hip endoprostheses may likely result in such cases.

[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.

Dynamic study of the finger interphalangeal joint volar plate-motion analysis with magnetic resonance cinematography and histologic comparison.

OBJECTIVE: We aimed to further improve knowledge about volar plate (VP) motion of the finger proximal interphalangeal joint (PIP), by analyzing the dynamic VP shape during a full range of finger flexion using magnetic resonance cinematography of the fingers (MRCF), and to compare the results with anatomical cross sections from cadaver specimens. MATERIALS AND METHODS: The dynamic sagittal VP shape was visualized with MRCF in a total number of 23 healthy volunteers. The length, angle, and thickness as well as the contact length of the VP to the PIP joint base were measured. Statistical analysis included t-test or rank-sum testing. Anatomical cross sections with differing degrees of PIP joint flexion were obtained from 12 cadaver specimens (fingers) for comparison. RESULTS: Significant positive correlations between PIP joint flexion angle and VP area, length, depth and the VP contact length were found. This matched histologically to fiber rearrangements especially within the loose third VP layer. CONCLUSION: Our study analyzed the full range of motion dynamic VP shape of the PIP joint using MRCF. This contributes to a more precise understanding of the complex interaction of the VP with the PIP joint and may facilitate evaluation of clinical cases such as VP avulsion or pulley rupture.

Assessment of the Value of Registries in Shoulder Arthroplasty Using Reverse Arthroplasty as an Example. / Die Wertigkeit von Endoprothesenregistern in der Schulterendoprothetik am Beispiel der inversen Endoprothese.

INTRODUCTION: As a consequence of the Swedish model, endoprosthesis registers have become increasingly important worldwide. Due to the increasing number of joint replacements at the shoulder, these are being increasingly included in the register databases - in addition to interventions at the hip and knee joint. In this study, the value of endoprosthesis registers is investigated, using the example of shoulder endoprosthetics and including a comparison with clinical studies. MATERIAL AND METHODS: The annual reports of 32 different endoprosthesis registers with data on hip, knee and/or shoulder arthroplasty were analysed. The number of operations and demographic patient data for all areas of endoprosthetics were examined. In addition, a more detailed consideration of variables such as the primary diagnosis, the cause of the revision, the revision rate depending on risk factors and patient-reported outcome measures (PROM scores) was carried out exclusively for the shoulder joint endoprostheses. Using the example of the inverse shoulder prosthesis, clinical studies were compared to registry data with special regard to the revision rate. RESULTS: A total of 20 endoprosthesis registers could be included, 9 of these collected data on shoulder arthroplasty. The main primary diagnoses were osteoarthritis (40.6%), rotator cuff defect arthropathy (30.2%) and fractures (17.6%). The most commonly used shoulder joint endoprosthesis was the inverse prosthesis (47.3%). The proportion of revision surgeries in total shoulder arthroplasty operations was less than 10% in all registers. In addition to the revision rate, the PROM scores were sometimes used in the registers to evaluate the success of the prosthesis. Compared to registry data, clinical studies showed more heterogeneous data with a significantly higher revision rate of over 10% in long-term follow-up - using the example of the inverse shoulder prosthesis. CONCLUSION: Register data are a valuable source of information in shoulder arthroplasty and can make a significant contribution to the quality assurance of endoprosthetic treatments. Compared to clinical studies, they primarily provide data on durability of different endoprosthesis and give lower revision rates. Clinical studies use PROM scores and clinical and radiological examinations to focus only on individual implants and surgical centres on the one hand and much more on the functional results on the other.

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.

Knot tying in arthroplasty and arthroscopy causes lesions to surgical gloves: a potential risk of infection.

PURPOSE: Recent studies have shown that the incidence of glove lesions during arthroscopy is much lower than that during primary and revision arthroplasty. However, the rate of glove damage after knot tying has not yet been systematically recorded. Therefore, the aim of the study was to determine the impact of surgical knot tying on glove integrity. It was hypothesized that knot tying increases the rate of glove damage, especially in arthroscopic surgery, which could be of special relevance in the treatment of rotator cuff tears. METHODS: Gloves that were changed immediately before suturing and only worn during knot tying were investigated for their integrity by means of water tightening test according to EN455. A total of 234 gloves from 40 total hip arthroplasties (THAs), 42 total knee arthroplasties (TKAs) and 36 rotator cuff repairs (RCRs) were collected. A bacterial pass-through test (BPTT) on glove lesions was performed under simulated sterile surgical conditions for 3 surgeons after a wear duration of 45 min. RESULTS: Glove damage by knot tying occurred in 25% of THA, 36.6% of TKA and 25% of RCR surgeries. In THA, the pulling hand (PH) was affected in 46.2%, and the main area of damage (15.4%) was detected on the tip of the middle finger; in TKAs the PH was damaged in 75%, and in RCRs the PH was affected in 66.7%, with most of the lesions (20% each) occurring on the tip of the index finger and the ring finger. The BPTT showed Staphylococcus hominis and Bacillus cereus. CONCLUSION: Intraoperative knot tying causes damage to gloves, which is of special relevance for arthroscopic surgery. Whereas knot tying is only partly responsible for glove damage in arthroplasty, the general rate of glove damage in arthroscopic surgery is low without knot tying. The surgical knot tying process must be understood as a possible damaging impact on the glove. Therefore, single gloving is not recommended, which is especially important in arthroscopic surgery, where double gloving is not yet standard. LEVEL OF EVIDENCE: IV.

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.

[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.

Comparison of the influence of supportive and sensorimotor insoles in the muscle activity of tibialis anterior and peroneus longus in combat boots.

INTRODUCTION: Flatfoot is a very common static deformity. It occurs frequently in soldiers and causes problems in the lower extremities. There is a lack of data regarding therapy with insoles, especially with sensorimotor insoles. The objective of this study was to investigate the influence in muscle activity of supporting/correcting and sensorimotor insoles in combat boots in the muscles of the lower limb and thus to draw conclusions according to the benefits of insole therapy in military footwear. METHODS: 73 patients (12 female, 61 males; average age: 30.8 ± 7.9 years) with pes planovalgus deformity were included in this prospective randomized placebo-controlled study. For intervention supporting (N = 23), sensorimotor (N = 28) and placebo insoles (N = 22) were used. During gait analysis muscle activity was measured by means of surface electromyography (EMG) of the tibialis anterior and peroneus longus muscle in combat boots with and without insoles. Statistical evaluation was performed using two-factor ANOVA with repeated measures. RESULTS: EMG measures (amplitude, integral, maximum, mean) showed mainly activating effects in the peroneus longus muscle in the case of sensorimotor and activity reductions in supporting insoles. Comparing effects of different kinds of insoles to the peroneus longus muscle, significant differences could be shown. No significant differences in muscular activation were observed for the tibialis anterior muscle. CONCLUSION: Even in combat boots effects of sensorimotor insoles on the peroneus longus muscle can be detected. The expected effects, attributed to the different kinds of insole, could be observed, too. While sensorimotor insoles had an activating kind of effect, supportive insoles reduced muscular activity of the peroneus longus. In contrast for the tibialis anterior muscle no clear conclusion could be drawn. Its muscular activity seems not to be influenced by insoles in combat boots. However, it remains unclear whether clinical long term effects, e.g. pain and function, can be improved.

[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.

Patellar Tracking in Total Knee Arthroplasty-Influence on Clinical and Functional Outcome.

Anterior knee pain is a common problem after primary total knee arthroplasty (TKA). The aim of this study was to find parameters in patellar positioning which influence the clinical and functional outcome after TKA. Included were 59 patients who underwent TKA, of which three patients were treated bilaterally (n = 62 included knees). In a periodical follow-up of up to 5 years, each patient had to answer three questionnaires (HSS, WOMAC, SF-36) and underwent three radiographies of the knee (including merchant view) and a clinical examination, including Range Of Motion (ROM). All radiographs were evaluated by a single observer blinded to clinical data, who collected multiple parameters of sagittal and axial patellar alignment including newly developed methods for measuring patellar shift and tilt. Depending on the measurement results, three groups were built for each parameter and the influence on the outcome was determined. A lateral patellar tilt of more than 4° resulted in lower scores for both the HSS and WOMAC. The rarely investigated patellar facet angle showed a significantly inferior clinical and functional outcome in late follow-up of >24 months if lower than 142°, possibly due to progressive osteosclerotic changes of the patella caused by increased contact stress with corresponding patellar morphology. No significant difference was found for all other parameters. The newly developed method for measuring patellar shift has proven to be a valuable and easy instrument in the postoperative setting.