Metal Artefact Reduction Sequences (MARS) in Magnetic Resonance Imaging (MRI) after Total Hip Arthroplasty (THA) : A non-invasive approach for preoperative differentiation between periprosthetic joint infection (PJI) and aseptic complications?

BACKGROUND: In the past, radiographic imaging was of minor relevance in the diagnosis of periprosthetic joint infections (PJI). Since metal artefact reduction sequences (MARS) are available, magnetic resonance imaging (MRI) has become a promising diagnostic tool for the evaluation of hip arthroplasty implants. The purpose of the present study was to evaluate the efficacy of MARS-MRI in comparison to established diagnostic tools to distinguish between aseptic failure and PJI. METHODS: From July 2018 to September 2019, 33 patients classified as having an aseptic joint effusion were recruited into the study. The group included 22 women and 11 men with a mean age of 70.4 ± 13.7 (42-88) years. In the same period, 12 patients were classified as having a PJI. The group consisted of 9 women and 3 men with a mean age of 72.5 ± 10.6 (54-88) years. MARS-MRI was conducted using the optimized parameters at 1.5 T in a coronal and axial STIR (short-tau-inversion recovery), a non-fat-saturated T2 in coronal view and a non-fat-saturated T1 in transverse view in 45 patients with painful hip after total hip arthroplasty (THA). Normally distributed continuous data were shown as mean ± standard deviation (SD) and compared using student's t-test. Non-normally distributed continuous data were shown as mean and compared using the Mann-Whitney U test. RESULTS: Synovial layering and muscle edema were significant features of periprosthetic joint infection, with sensitivities of 100% and specifities of 63.0-75.0%. The combined specifity and sensitivity levels of synovial layering and muscular edema was 88.0% and 90.0%. Granulomatous synovitis was a significant feature for aseptic failure, with 90.0% sensitivity and 57.0% specifity. CONCLUSION: MARS-MRI is as suitable as standard diagnostic tools to distinguish between aseptic failure and PJI in patients with THA. Further studies with larger patient numbers have to prove whether MARS-MRI could be integral part of PJI diagnostic.

[Shoulder arthroplasty]. / Schulterendoprothetik.

Arthroplasty of the shoulder joint leads to excellent clinical results if the indications are valid and the implantation is technically correct. Taking anatomical requirements and mechanical functions as well as material properties and developments in surgical techniques into account, articulations and anchoring systems have been developed which, as modular systems enable successful restoration of the biomechanics and consider the importance of the surrounding soft tissues. Scientific data show promising medium-term and long-term results in terms of functionality and pain reduction. Nevertheless, due to the limited bone stock for implant anchoring, especially loosening of the prosthesis or instability of the glenoid joint component, revision arthroplasty remains challenging. This review article summarizes the relevant aspects of shoulder arthroplasty.

Elucidating vulnerability to inflammation-induced hyperalgesia: Predictors of increased musculoskeletal pain sensitivity during experimental endotoxemia.

Despite broad clinical implications, the mechanisms linking inflammation and pain remain incompletely understood. Using human experimental endotoxemia as a translational model of systemic inflammation, we aimed to elucidate putative vulnerability factors of inflammation-induced musculoskeletal hyperalgesia. We pooled data from three published randomized controlled trials, resulting in a sample of N = 98 healthy volunteers who received either low-dose endotoxin (lipopolysaccharide) or vehicle (saline) intravenously. As measure of musculoskeletal pain sensitivity, pressure pain thresholds (PPTs) were assessed at baseline and 3 h post injection with a handheld algometer for the low back (erector spinae muscle), calf (gastrocnemius muscle), and shoulder region (deltoid muscle). Implementing multiple regression models, we tested the contribution of putative vulnerability factors on musculoskeletal hyperalgesia during systemic inflammation, including acute changes in pro-inflammatory cytokines, state anxiety and mood, as well as pre-existing symptoms of anxiety and depression. Endotoxin application led to significant increases in plasma cytokines, state anxiety, and negative mood, and significantly decreased PPTs for all muscle groups. Regression models revealed that greater M. erector spinae PPT changes were predicted by higher HADS-anxiety scores. Higher TNF-α concentration emerged as predictor for M. gastrocnemius PPT changes, and more pronounced TNF-α increase and higher HADS-anxiety were predictive for M. deltoideus PPTs. HADS scores emerged as predictor for a mean PPT score (computed across all body sites). Together, our results indicate that musculoskeletal hyperalgesia during systemic inflammation is related to pro-inflammatory cytokines, specifically TNF-α. Importantly, subclinical anxiety symptoms (even though in a low and normal range in this cohort of healthy volunteers) may contribute to inflammation-induced hyperalgesia, making individuals more vulnerable to the detrimental effects of systemic inflammation.

Impact of acute inflammation on the extinction of aversive gut memories.

Impaired extinction of pain-related fear memories can lead to persistent or resurging fear of pain, contributing to the development and maintenance of chronic pain conditions. The mechanisms underlying maladaptive pain-related learning and memory processes remain incompletely understood, particularly in the context of interoceptive, visceral pain. Inflammation is known to interfere with learning and memory, but its effects on the extinction of pain-related fear memories have never been tested. In a randomized, double-blind, placebo-controlled study, we assessed the impact of experimental acute inflammation on the extinction and reinstatement of conditioned visceral pain-related fear. Forty healthy male volunteers underwent differential fear conditioning with visceral pain as clinically relevant unconditioned stimulus (US). Participants then received an intravenous injection of either 0.8 ng/kg lipopolysaccharide (LPS) as inflammatory stimulus or physiological saline as placebo, and extinction training was conducted at the peak of the inflammatory response. Extinction recall and reinstatement test were performed after overnight consolidation. Results showed that visceral pain represents an effective US, eliciting pronounced conditioned pain-related fear responses. Repeated unreinforced presentation of the pain-predictive cue during extinction training resulted in full extinction of the conditioned behavioral response. However, unexpected re-exposure to the US during reinstatement test resulted in return of fear. Despite pronounced LPS-induced effects on inflammatory markers, cortisol, and negative affect, we did not find evidence that acute inflammation resulted in altered fear extinction. The findings support the notion that visceral pain-related fear learning establishes a robust aversive memory trace that remains preserved during inhibitory learning, leaving a latent vulnerability for the return of fear. Inflammation during inhibitory learning did neither weaken nor further amplify this aversive memory trace, suggesting that it is rather resistant to acute inflammation-induced effects, at least in healthy individuals with no additional vulnerability factors.

Is Procalcitonin (PCT) a reliable biomarker for preoperative diagnosing of low grade periprosthetic joint infection? A prospective study.

BACKGROUND: Since a "gold-standard" is missing, diagnosing periprosthetic joint infection (PJI) remains a challenge in orthopedic surgery. The purpose of this study was to evaluate the accuracy of serum and synovial fluid Procalcitonin (S-PCT and SF-PCT) as a diagnostic parameter and to compare it to the biomarkers recommended in the 2018 Definition of periprosthetic hip and knee infection. METHODS: Between August 2018 and July 2019, a prospective cohort study was conducted in 70 patients with painful hip, shoulder and knee arthroplasty. Besides medical history, clinical and laboratory data was gathered. PJI was diagnosed based on the 2018 Definition of periprosthetic hip and knee infection. Preoperative blood and synovial joint fluid were taken for PCT measurement. S-PCT and SF-PCT levels were measured using standard quantitative PCT enzyme immunoassays. RESULTS: Twenty three patients (33%) were classified as the PJI group and fourty seven patient (67%) as the aseptic group. The mean levels of S-PCT were significantly (p <  0.001) higher in the PJI group than those in the aseptic group (PJI 0.05 ± 0.21 ng/mL (0.0-1.03) vs. aseptic 0.02 ± 0.03 ng/mL (0.0-0.18)). In synovial fluid, the mean PCT values in the aseptic group were significantly higher (p <  0.001) than those of PJI group (PJI 2.7 ± 1.4 ng/mL (0.53-9.7) vs. aseptic 8.7 ± 2.5 ng/mL (0.25-87.9)). S- PCT, with a cut-off level of 0.5 ng/mL, had a sensitivity of 13.0% and a specificity of 91.0%. SF-PCT, with a cut-off level of 5.0 ng/mL, had a sensitivity of 13.0% and a specificity of 52.0%. CONCLUSION: S-PCT and SF-PCT appeared to be no reliable biomarkers in the differential diagnosis of PJI from aseptic loosening in total joint arthroplasty.

Vitamin E-blended versus conventional polyethylene liners in prostheses : Prospective, randomized trial with 3-year follow-up.

BACKGROUND: Despite continuous technical improvements, polyethylene wear debris induced periprosthetic osteolysis remains the main cause for failure of hip arthroplasty. Progressive oxidation of polyethylene was identified as another risk factor for material failure. To overcome this problem, antioxidants such as vitamin E (alpha-tocopherol) were supplemented by diffusion into the latest generation of polyethylene liners. OBJECTIVE: The purpose of the present study was to investigate the clinical outcome of patients treated with vitamin E blended highly cross-linked ultra-high molecular weight polyethylene liners (UHMWPE-XE) in comparison with conventional UHMWPE­X liners by evaluating patient-reported outcome measures (PROM's) at 3­year follow-up. METHODS: A total of 143 patients were recruited into this prospective, randomized trial in our academic center. Three years after implantation, 101 patients were examined in the outpatient clinic for follow-up. Of these, 51 (50.5%) received UHMWPE-XE and 50 (49.5%) UHMWPE­X liners. Clinical outcome was evaluated using Harris-Hip-Score (HHS) UCLA-Score and Hip Disability and Osteoarthritis Outcome Score (HOOS). RESULTS: There was a significant improvement in all PROM's at one- and three-year follow-up compared to the status before implantation. PROM's did not differ significantly between the first and third year follow-up. Both liner groups showed an equal clinical outcome. CONCLUSION: The present study demonstrates that the supplementation of vitamin E to polyethylene liners is reliable and safe without showing higher complication rates compared with conventional polyethylene liners. The shortterm clinical outcome of vitamin E-blended (UHMWPE­XE) is equivalent to those of conventional highly cross-linked polyethylene liners.

Long-term results of the reverse Total Evolutive Shoulder System (TESS).

INTRODUCTION: Latest trends in shoulder replacement aim at bone stock preservation. Long-term results of stemless anatomical total shoulder implants compare favourably with stemmed designs in terms of function and survivorship. The Total Evolutive Shoulder System (TESS) has been one of the first designs offering a stemless implant not only for anatomical but also for reverse total shoulder arthroplasty with optional short stem attachment in cases with poor bone quality. The aim of the present study was to evaluate long-term results of the reverse Total Evolutive Shoulder System (TESS). MATERIALS AND METHODS: Between 2006 and 2009, 49 shoulders in 47 patients were replaced using the Biomet reverse Total Evolutive Shoulder System (TESS). 29 shoulders in 27 patients who were aged 72.4 ± 6.7 (53-88) years were available for review at a mean follow-up of 101.6 ± 24.6 (75-142) months. RESULTS: The implant survival rate was 93.1% at 101 months (8.4 years). The overall revision rate of the TESS implant was 17.2%. No implant associated complications to the reverse corolla implant could be observed. All reverse corolla implants showed solid fixation at follow-up. Scapular notching was found in 72.3% of the shoulders. Clinical scores significantly improved at long-term follow-up (VAS from 7.5 ± 1.2 to 1.4 ± 1.5, p < 0.001; quick-DASH from 70.9 ± 12.0 to 28.9 ± 22.9, p < 0.001 and Constant score from 13.0 ± 3.7 to 60.5 ± 16.8, p < 0.001). CONCLUSIONS: In terms of clinical scores, radiographic loosening, complication rates and implant survivorship the reverse Total Evolutive Shoulder System provides results comparable to those of conventional stemmed reverse shoulder arthroplasty.

Willingness of medical students to be examined in a physical examination course.

BACKGROUND: Physical examination courses are an essential part of the education of medical students. The aim of this study was to ascertain the factors influencing students' motivation and willingness to participate in a physical examination course. METHODS: Students were asked to complete a questionnaire subdivided into five domains: anthropometric data, religiousness, motivation to take part in physical examination courses, willingness to be physically examined at 11 different body regions by peers or a professional tutor and a field for free text. RESULTS: The questionnaire was completed by 142 medical students. The importance of the examination course was rated 8.7 / 10 points, the score for students' motivation was 7.8 / 10 points. Willingness to be physically examined ranged from 6 to 100% depending on body part and examiner. Female students were significantly less willing to be examined at sensitive body parts (breast, upper body, groin and the hip joint; p = .003 to < .001), depending on group composition and / or examiner. Strictly religious students showed significantly less willingness to undergo examination of any part of the body except the hand (p = .02 to < .001). Considering BMI, willingness to be examined showed comparable rates for normal weight and under- / overweight students in general (80% vs. 77%). Concerning the composition of the group for physical examination skills courses, students preferred self-assembled over mixed gender and same gender groups. CONCLUSIONS: Peer physical examination is a method to improve students' skills. While motivation to participate in and acceptance of the physical examination course appears to be high, willingness to be examined is low for certain parts of the body, e.g. breast and groin, depending on religiousness, gender and examiner. Examination by a professional medical tutor did not lead to higher acceptance. Most students would prefer to choose their team for physical examination courses themselves rather than be assigned to a group.

Long-term survivorship of stemless anatomical shoulder replacement.

PURPOSE: Like in many other joints, current shoulder replacement designs aim at bone preservation. According to the literature available, stemless total shoulder arthroplasty (TSA) compares favourably with stemmed designs in terms of function and survivorship of the implant. However, long-term results of stemless shoulder arthroplasty are still missing. Therefore, the aim of the present study was to evaluate long-term results of stemless anatomical TSA. METHODS: Between 2006 and 2009, 51 shoulders in 46 patients were resurfaced using the Biomet Total Evolutive Shoulder System (TESS). Thirty-one shoulders in 26 patients who were aged 66.7 ± 10.0 (range 34-82) years were available for review at a mean follow-up of 94.7 ± 11.3 (76-124) months. RESULTS: The implant survival rate was 93.5% at eight years. The overall revision rate of the TESS implant was 9.7%. Radiolucent lines were found on the glenoid side of the TESS arthroplasty in 90.9% of the cases. All stemless humeral corolla implants showed solid fixation at follow-up. Clinical scores significantly improved at long-term follow-up (VAS from 8.1 ± 0.9 to 1.0 ± 1.2, p < 0.001; Quick-DASH from 67.9 ± 13.5 to 18.7 ± 16.5, p < 0.001 and Constant score from 14.7 ± 6.1 to 68.8 ± 13.2, p < 0.001). CONCLUSIONS: Stemless TSA has stood the test of time at eight years in terms of clinical scores, radiographic loosening, complication rates and implant survivorship.

Men and women differ in inflammatory and neuroendocrine responses to endotoxin but not in the severity of sickness symptoms.

Impaired mood and increased anxiety represent core symptoms of sickness behavior that are thought to be mediated by pro-inflammatory cytokines. Moreover, excessive inflammation seems to be implicated in the development of mood/affective disorders. Although women are known to mount stronger pro-inflammatory responses during infections and are at higher risk to develop depressive and anxiety disorders compared to men, experimental studies on sex differences in sickness symptoms are scarce. Thus, the present study aimed at comparing physiological and psychological responses to endotoxin administration between men and women. Twenty-eight healthy volunteers (14 men, 14 women) were intravenously injected with a low dose (0.4 ng/kg) of lipopolysaccharide (LPS) and plasma concentrations of cytokines and neuroendocrine factors as well as negative state emotions were measured before and until six hours after LPS administration. Women exhibited a more profound pro-inflammatory response with significantly higher increases in tumor necrosis factor (TNF)-α and interleukin (IL)-6. In contrast, the LPS-induced increase in anti-inflammatory IL-10 was significantly higher in men. The cytokine alterations were accompanied by changes in neuroendocrine factors known to be involved in inflammation regulation. Endotoxin injection induced a significant increase in noradrenaline, without evidence for sex differences. The LPS-induced increase in cortisol was significantly higher in woman, whereas changes in dehydroepiandrosterone were largely comparable. LPS administration also increased secretion of prolactin, but only in women. Despite these profound sex differences in inflammatory and neuroendocrine responses, men and women did not differ in endotoxin-induced alterations in mood and state anxiety or non-specific sickness symptoms. This suggests that compensatory mechanisms exist that counteract the more pronounced inflammatory response in women, preventing an exaggerated sickness response. Disturbance of these compensatory mechanisms by environmental factors such as stress may promote the development of affective disorders in women.

Neural circuitry mediating inflammation-induced central pain amplification in human experimental endotoxemia.

BACKGROUND & AIMS: To elucidate the brain mechanisms underlying inflammation-induced visceral hyperalgesia in humans, in this functional magnetic resonance imaging (fMRI) study we tested if intravenous administration of lipopolysaccharide (LPS) involves altered central processing of visceral pain stimuli. METHODS: In this randomized, double-blind, placebo-controlled fMRI study, 26 healthy male subjects received either an intravenous injection of low-dose LPS (N=14, 0.4 ng/kg body weight) or placebo (N=12, control group). Plasma cytokines (TNF-α, IL-6), body temperature, plasma cortisol and mood were assessed at baseline and up to 6 h post-injection. At baseline and 2 h post-injection (test), rectal pain thresholds and painful rectal distension-induced blood oxygen level-dependent (BOLD) responses in brain regions-of-interest were assessed. To address specificity for visceral pain, BOLD responses to non-painful rectal distensions and painful somatic stimuli (i.e., punctuate mechanical stimulation) were also analyzed as control stimuli. RESULTS: Compared to the control group, LPS-treated subjects demonstrated significant and transient increases in TNF-α, IL-6, body temperature and cortisol, along with impaired mood. In response to LPS, rectal pain thresholds decreased in trend, along with enhanced up-regulation of rectal pain-induced BOLD responses within the posterior insula, dorsolateral prefrontal (DLPFC), anterior midcingulate (aMCC) and somatosensory cortices (all FWE-corrected p<0.05). Within the LPS group, more pronounced cytokine responses correlated significantly with enhanced rectal pain-induced neural activation in DLPFC and aMCC. No significant LPS effects were observed on neural responses to non-painful rectal distensions or mechanical stimulation. CONCLUSIONS: These findings support that peripheral inflammatory processes affect visceral pain thresholds and the central processing of sensory-discriminative aspects of visceral pain.

Inflammation-induced hyperalgesia: effects of timing, dosage, and negative affect on somatic pain sensitivity in human experimental endotoxemia.

BACKGROUND: Inflammation-induced pain amplification and hypersensitivity play a role in the pathophysiology of numerous clinical conditions. Experimental endotoxemia has recently been implemented as model to analyze immune-mediated processes in human pain. In this study, we aimed to analyze dose- and time-dependent effects of lipopolysaccharide (LPS) on clinically-relevant pain models for musculoskeletal and neuropathic pain as well as the interaction among LPS-induced changes in inflammatory markers, pain sensitivity and negative affect. METHODS: In this randomized, double-blind, placebo-controlled study, healthy male subjects received an intravenous injection of either a moderate dose of LPS (0.8 ng/kg Escherichiacoli), low-dose LPS (0.4 ng/kg), or saline (placebo control group). Pressure pain thresholds (PPT), mechanical pain sensitivity (MPS), and cold pain sensitivity (CP) were assessed before and 1, 3, and 6h post injection to assess time-dependent LPS effects on pain sensitivity. Plasma cytokines (TNF-α, IL-6, IL-8, IL-10) and state anxiety were repeatedly measured before, and 1, 2, 3, 4, and 6h after injection of LPS or placebo. RESULTS: LPS administration induced a systemic immune activation, reflected by significant increases in cytokine levels, body temperature, and negative mood with pronounced effects to the higher LPS dose. Significant decreases of PPTs were observed only 3h after injection of the moderate dose of LPS (0.8 ng/kg). MPS and CP were not affected by LPS-induced immune activation. Correlation analyses revealed that decreased PPTs were associated with peak IL-6 increases and negative mood. CONCLUSIONS: Our results revealed widespread increases in musculoskeletal pain sensitivity in response to a moderate dose of LPS (0.8 ng/kg), which correlate both with changes in IL-6 and negative mood. These data extend and refine existing knowledge about immune mechanisms mediating hyperalgesia with implications for the pathophysiology of chronic pain and neuropsychiatric conditions.

[Injuries in the First German Inline Skater Hockey League]. / Verletzungen in der 1. Inline-Skaterhockey-Bundesliga.

Inline skater hockey is a sport originating from ice hockey, which is practised in Germany by about 6000 athletes. There are some differences to ice hockey, which lead to a special risk profile of the athletes.All 315 active players of the First German Inline Skater Hockey League in the years 2018 and 2019 were contacted to participate in an online survey. The subjects of the study completed an anonymised 83-item multiple-choice questionnaire about injuries, training frequency, training content, and sports equipment. 178 athletes responded and 116 questionnaires could be analysed (100 men, 8 women, 8 without information/16 goalies, 55 forwards, 44 defenders).The overall injury incidence was 36.98 per 1000 hours. Minor injuries (wounds, bruises, and blunt muscle injuries) most frequently comprised leg injuries (9.4/1000 hours) and arm injuries (7.2/1000 hours). Relevant injuries (fractures, dislocations, and ligamentous injuries) were most common to the foot (2.4/1000 hours) (n=147) and to the head (1.9/1000 hours) (n=140) and knee (1.7/1000 hours) (n=126). Of 76 fractures, 48 (63.2%) resulted from direct or indirect body contact. Goalkeepers suffered more knee injuries compared with field players, while field players sustained more shoulder injuries. Head injuries (fractures, dental injuries, traumatic brain injuries) were significantly more frequent in players without face protection (3.0/1000h vs. 1.8/1000h). Players who did not perform additional fitness training had significantly more relevant injuries. In this group, knee injuries occurred more frequently as well (4.2/1000h vs. 1.3/1000h). The duration of stretching exercises showed a negative correlation with overall injury incidence (0 minutes: 53.5/1000 hours, 1-4 minutes: 55.8/1000 hours, 5-9 minutes: 23.5/1000 hours, ≥10 minutes: 21.5/1000 hours, p<0.05).In particular, mild injuries occurred with a highly significant reduction in frequency if the subjects performed stretching exercises. Inline skater hockey in the First German League is characterised by a high risk of injury, which can be compared with professional ice hockey. Serious injuries are mainly caused by physical contact. Relevant injuries are most common to the head and lower extremity. The implementation of fitness training had a positive influence on the frequency of injuries. In the context of further professionalisation of this sport, these findings can contribute to the prevention of injuries in inline skater hockey.

Single-trial conditioning in a human taste-endotoxin paradigm induces conditioned odor aversion but not cytokine responses.

Immunological responses to bacterial endotoxin can be behaviorally conditioned in rodents. However, it is unclear whether an acute systemic inflammatory response can be behaviorally conditioned in humans. Thus, in a double-blind placebo-controlled study, 20 healthy, male subjects received either a single injection of lipopolysaccharide (LPS) or saline together with a novel tasting beverage (conditioned stimulus, CS). Five days later, all subjects received a saline injection and were re-exposed to the CS. Blood was drawn prior to as well as 0.5, 1.5, 3, 4, 6, and 24 h after LPS administration or CS re-exposure. Endotoxin administration led to transient increases in plasma concentrations of interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-α and to a significant rise in body temperature. Sole presentation of the CS during evocation did induce neither alterations in body temperature nor changes in plasma cytokine levels. However, subjects in the experimental group rated the smell of the CS significantly more aversive compared to the control group. Employing endotoxin as a US in a single trial taste-immune conditioning paradigm in humans shows a behaviorally conditioned smell aversion but no learned alterations in cytokine levels.

SuperPath® vs. direct anterior approach : A retrospective comparison between two minimally invasive approaches in total hip arthroplasty.

OBJECTIVE: Minimally invasive approaches are subject to controversy in orthopedic surgery. The aim of the current study was to compare the radiographic parameters between two minimally invasive approaches in total hip arthroplasty. MATERIAL AND METHODS: Between January 2018 and February 2019, the radiographic parameters of 80 patients undergoing total hip arthroplasty via minimally invasive approaches (DAA: n = 40; SuperPath® SP: n = 40) have been measured. The radiographic analysis was performed with digital software tool mediCad® (HECTEC™ GmbH, Landshut, Germany). RESULTS: Patients treated with DAA showed significantly higher inclination (SP: 39.7°â€¯± 7.3° vs. DAA: 44.7°â€¯± 5.3°) and significantly lower cup anteversion values (SP: 31.2°â€¯± 7.9° vs. DAA: 27. 5°â€¯± 5.3°, p < 0.001) than patients undergoing THA via SP postoperatively. The horizontal femoral offset was neither preoperatively nor postoperatively higher in DAA than in SP cohort (preoperative: p = 0.71, postoperative: p = 0.25) (preoperative: SP:37.2 mm ± 7.3 vs. DAA 38.2 mm ± 7.5; postoperative: SP: 38.0 mm ± 7.2 vs. DAA: 40.5 mm ± 7.0). At both times, the acetabular offset was significantly higher in DAA cohort than in SP cohort (preoperative: SP: 32.9 mm ± 5.9 vs. DAA: 36.8 mm ± 4.9; postoperative: SP: 28.9 mm ± 4.2 vs. DAA: 33.4 mm ± 3.8) (preoperative: 0.001; postoperative: p < 0.001). The vertical height was preoperatively and postoperatively not significantly higher in SP cohort than in DAA cohort (preoperative: SP: 16.1 mm ± 4.1 vs. DAA: 15.5 mm ± 4.9; postoperative: SP: 16.6 mm ± 4.6 vs. DAA: 16.1 mm ± 4.6) (preoperative: p = 0.77; postoperative: p = 0.58). The preoperatively existing leg length discrepancy of the affected leg could be compensated via surgery without showing significant differences between the two cohorts (preoperative: SP: -3.2 mm ± 5.4 vs. DAA: 1.9 mm ± 4.9; postoperative: SP: 1.5 mm ± 5.4 vs. DAA: 4.8 mm ± 5.6) (preoperative: p = 0.34; postoperative: p = 0.09). CONCLUSION: The current study demonstrates suitable cup positioning and stem alignment in the coronal plane using minimal-invasive approaches DAA and Superpath®.

Diagnostic Accuracy of Synovial Neopterin, TNF-α and Presepsin in Periprosthetic Joint Infection: A Prospective Study.

BACKGROUND: Due to the lack of specificity of conventional diagnostic tools, the prediction of periprosthetic joint infections (PJI) remains challenging. The purpose of this study was to evaluate the accuracy of synovial fluid neopterin, presepsin, and TNF-α as diagnostic parameters and to compare it to the biomarkers recommended in the 2018 definition of periprosthetic hip and knee infection. METHODS: Between August 2018 and July 2019, a prospective cohort study was conducted in 80 patients with painful hip, shoulder, and knee arthroplasty. In addition to medical history, clinical and laboratory data were gathered. PJI was diagnosed based on the 2018 definition of periprosthetic hip and knee infection. Synovial joint fluid was analyzed for biomarker measurement using standard quantitative enzyme immunoassay kits. RESULTS: Fifty-three patients (66%) were classified as the aseptic group and twenty-seven patients (34%) as the PJI group. The mean levels of synovial fluid neopterin were significantly higher (p < 0.01) in the PJI group than those in the aseptic group (aseptic 8.3 ± 6.9 vs. PJI 20.9 ± 21.4 nmol/L). The average values of synovial fluid TNF-α and presepsin were not significantly higher in the PJI group than those in the aseptic group (presepsin: aseptic 0.13 ± 0.19 vs. PJI 0.11 ± 0.32 ng/mL, p = 0.08; TNF-α: aseptic 6.6 ± 7.3 vs. PJI 46.3 ± 123.2 pg/mL, p = 0.17). Synovial fluid neopterin was 59% specific and 74% sensitive with a cut-off value of 7.2 nmol/L. The sensitivity and specificity of synovial fluid TNF-α were 63 and 51% with a cut-off value of 3.9 pg/mL. Synovial fluid presepsin was 51% specific and 29% sensitive with a cut-off value above 0.06 ng/mL. CONCLUSION: Synovial fluid neopterin appears to a reliable diagnostic marker for detection of PJI. In contrast, synovial fluid TNF-α and presepsin are not suitable to exclude or diagnose PJI.

Incidence, impact and risk factors for multidrug-resistant organisms (MDRO) in patients with major trauma: a European Multicenter Cohort Study.

INTRODUCTION: The burden of MDRO in health systems is a global issue, and a growing problem. We conducted a European multicenter cohort study to assess the incidence, impact and risk factors for multidrug-resistant organisms in patients with major trauma. We conducted this study because the predictive factors and effects of MDRO in severely injured patients are not yet described. Our hypothesis is that positive detection of MDRO in severely injured patients is associated with a less favorable outcome. METHODS: Retrospective study of four level-1 trauma centers including all patients after major trauma with an injury severity score (ISS) ≥ 9 admitted to an intensive care unit (ICU) between 2013 and 2017. Outcome was measured using the Glasgow outcome scale (GOS). RESULTS: Of 4131 included patients, 95 (2.3%) had a positive screening for MDRO. Risk factors for MDRO were male gender (OR 1.73 [95% CI 1.04-2.89]), ISS (OR 1.01 [95% CI 1.00-1.03]), PRBC's given (OR 1.73 [95% CI 1.09-2.78]), ICU stay > 48 h (OR 4.01 [95% CI 2.06-7.81]) and mechanical ventilation (OR 1.85 [95% CI 1.01-3.38]). A positive MDRO infection correlates with worse outcome. MDRO positive cases GOS: good recovery = 0.6%, moderate disability = 2.1%, severe disability = 5.6%, vegetative state = 5.7% (p < 0.001). CONCLUSIONS: MDRO in severely injured patients are rare but associated with a worse outcome at hospital discharge. We identified potential risk factors for MDRO in severely injured patients. Based on our results, we recommend a standardized screening procedure for major trauma patients.

Femoral component rotation in patients with leg axis deviation.

PURPOSE: Correct alignment of the rotation of the femoral component and the flexion gap after total knee arthroplasty is difficult in patients with preoperative leg axis deviation. Inaccuracy may result in problems with the patellofemoral joint and instability, in particular. We examined the influence of the preoperative leg axis on the rotation of the femoral component and the symmetry of the flexion gap after total knee arthroplasty using the tibial-cut-first technique. METHODS: A retrospective study was carried out of 58 consecutive patients who underwent primary LCS total knee arthroplasty using the tibial-cut-first technique in 2008 based on preoperative full-leg radiographs and the final radiographs taken according to Kanekasu's technique. The patients were divided into three groups (varus-valgus-neutral) according to their preoperative leg axis. RESULTS: Using the tibial-cut-first technique, a mean neutral rotation of the femoral component of 0.5° and a mean symmetrical flexion gap of -0.7° were achieved. Nevertheless, there was a positive correlation of the preoperative leg axis with the rotation of the femoral component. The differences in the rotation of the femoral component and the flexion gap between the three groups were not significant. The only significant difference between the varus and valgus groups was the extent of rotation of the femoral component, with a slightly greater external rotation of 2.7° in the valgus group. CONCLUSIONS: This study suggests that it is possible to achieve correct rotational alignment of the femoral component and a symmetrical flexion gap using the tibial-cut-first technique in patients with a preoperatively deviated leg axis.

Bone Substitutes in Orthopaedic Surgery: Current Status and Future Perspectives.

Bone replacement materials have been successfully supplied for a long time. But there are cases, especially in critical sized bone defects, in which the therapy is not sufficient. Nowadays, there are multiple bone substitutes available. Autologous bone grafts remain the "gold standard" in bone regeneration. Yet, donor-site morbidity and the available amount of sufficient material are limitations for autologous bone grafting. This study aimed to provide information about the current status in research regarding bone substitutes. We report on the advantages and drawbacks of several bone substitutes. At the end, we discuss the current developments of combining ceramic substitutes with osteoinductive substances.

Long-Term Radiographic Changes in Stemless Press-Fit Total Shoulder Arthroplasty.

INTRODUCTION: Stemmed humeral implants have represented the gold standard in total shoulder arthroplasty (TSA) for decades. Like many other joints, the latest trends in TSA designs aim at bone preservation. Current studies have demonstrated that native proximal humeral bone stresses are most closely mimicked by stemless implants. Nevertheless, there are concerns about the long-term performance of stemless designs. The aim of the present study was to evaluate the long-term radiographic changes at the proximal humerus in anatomical stemless press-fit TSA. MATERIALS AND METHODS: Between 2008 and 2010, 48 shoulders in 43 patients were resurfaced using an anatomic stemless shoulder prosthesis (TESS, Biomet). Thirty shoulders in twenty-five patients who were aged 65.7 ± 9.9 (34 to 82) years were available for clinical and radiographic review at a mean follow-up of 94.0 ± 8.9 (78 to 110) months. RESULTS: Radiographic changes of the proximal humerus due to stress shielding were found in 38.4% of the stemless TESS implants. Mild stress shielding accounted for 80% of the observed radiographic changes. Radiographs exhibited stable fixation of the stemless humeral press-fit implant at early and late follow-up. In contrast, radiolucent lines at the glenoid implant were found in 96.1% of the cases. Irrespective of the degree of radiographic changes, clinical scores (VAS, Quick-DASH, Constant score) significantly improved at follow-up. CONCLUSIONS: The anatomic stemless press-fit implant seems to be favorable in terms of implant-related stress shielding. Clinical outcome was not affected by radiographic changes, demonstrating an 8-year clinical performance that seems to be comparable to conventional stemmed TSA.