Comparison between dedicated MRI and symphyseal fluoroscopic guided contrast agent injection in the diagnosis of cleft sign in athletic groin pain and association with pelvic ring instability

OBJECTIVE

To compare dedicated MRI with targeted fluoroscopic guided symphyseal contrast agent injection regarding the assessment of symphyseal cleft signs in men with athletic groin pain and assessment of radiographic pelvic ring instability.

METHODS

Sixty-six athletic men were prospectively included after an initial clinical examination by an experienced surgeon using a standardized procedure. Diagnostic fluoroscopic symphyseal injection of a contrast agent was performed. Additionally, standing single-leg stance radiography and dedicated 3-Tesla MRI protocol were employed. The presence of cleft injuries (superior, secondary, combined, atypical) and osteitis pubis was recorded.

RESULTS

Symphyseal bone marrow edema (BME) was present in 50 patients, bilaterally in 41 patients and in 28 with an asymmetrical distribution. Comparison of MRI and symphysography was as followed: no clefts: 14 cases (MRI) vs. 24 cases (symphysography), isolated superior cleft sign: 13 vs. 10, isolated secondary cleft sign: 15 vs. 21 cases and combined injuries: 18 vs. 11 cases. In 7 cases a combined cleft sign was observed in MRI but only an isolated secondary cleft sign was visible in symphysography. Anterior pelvic ring instability was observed in 25 patients and was linked to a cleft sign in 23 cases (7 superior cleft sign, 8 secondary cleft signs, 6 combined clefts, 2 atypical cleft injuries). Additional BME could be diagnosed in 18 of those 23.

CONCLUSION

Dedicated 3-Tesla MRI outmatches symphysography for purely diagnostic purposes of cleft injuries. Microtearing at the prepubic aponeurotic complex and the presence of BME is a prerequisite for the development of anterior pelvic ring instability.

CLINICAL RELEVANCE STATEMENT

For diagnostic of symphyseal cleft injuries dedicated 3-T MRI protocols outmatch fluoroscopic symphysography. Prior specific clinical examination is highly beneficial and additional flamingo view x-rays are recommended for assessment of pelvic ring instability in these patients.

KEY POINTS

• Assessment of symphyseal cleft injuries is more accurate by use of dedicated MRI as compared to fluoroscopic symphysography. • Additional fluoroscopy may be important for therapeutic injections. • The presence of cleft injury might be a prerequisite for the development of pelvic ring instability.

What makes an orthopaedic paper highly citable? A bibliometric analysis of top orthopeadic journals with 10-year follow up

PURPOSE

To examine a series of papers from top ranked orthopaedic journals with respect to the number of citations over a 10-year observation period to identify factors that lead to high citation rates.

METHODS

The Web of Science database was consulted to identify all published papers from the first-year term of 2010 (January-May) from four top orthopaedic journals: AJSM, Arthroscopy, JBJS Am and KSSTA. The database was used to analyze and compare the papers with respect to their characteristics and citations up to 2019. Basic information for each paper was collected including the author, country, study type and average citations per year (ACY). The most (Top20%) and least (Bottom20%) frequently cited papers were identified and differences were extracted.

RESULTS

Five hundred sixteen papers were included with a total of 19,261 citations. Most of the published papers were from the United States (n = 245). On average, a paper received 37.3 citations over the 10-year observation period. The most cited paper was cited 322 times. The most cited study type was randomized controlled trial (RCT) (Ø80.8). The Top20% papers were cited 37 times more often than the Bottom20%. Among the Top20%, the largest group was cohort study (n = 20) followed by case series (n = 19). Among others, the number of authors, the number of keywords and the number of references significantly correlated with the number of citations (p < 0.001).

CONCLUSIONS

Factors influencing citation frequency were identified.

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.

[Individual megaspacers in two-stage revision of infected total hip arthroplasty-clinical and functional results after 2 years : Individual metal-endoskeleton cement spacer (iMECS)]

BACKGROUND

Large femoral defects in late periprosthetic infection (PPI) after total hip arthroplasty (THA) often require the use of large, individual metal endoskeleton-reinforced cement spacers (iMECS).

OBJECTIVES

The aim was to record the clinical, radiological and functional results (Harris Hip Score HHS) up to the 2 years after treatment of a PPI using an iMECS. Major patient-specific parameters were to be evaluated with regard to the treatment outcome.

MATERIALS AND METHODS

The collective of this single-center retrospective cohort study comprised 29 patients. The mean follow-up was 24.4 months (range: 23.0 to 27.6 months). The absence of infection after endoprosthetic hip joint reconstruction was rated as successful treatment. The two patient groups (successful (S)/not successful (nS)) were compared with regard to gender distribution, the Charlson comorbidity index (CCI), the number of previous septic changes, and the rate of polymicrobial and difficult-to-treat infections.

RESULTS

The average CCI in the total collective was 6.4 points. Joint reconstruction was possible in 23 of 29 patients (79%); 2 years after PPI treatment 4 patients were not available for a follow-up examination (2 deceased, 2 unable to participate). At the time of the follow-up, 17 of the 29 patients had received a joint reconstruction and were free of infection, with an average HHS of 75 points. There were no iMECS-associated complications requiring revision. Only the initial CCI (S: 4.1 points; nS: 9.7 points) differed significantly between the patient groups (p < 0.05).

CONCLUSIONS

In the case of large femoral defects, iMECS provide secure temporary stabilization. The chance of a successful joint reconstruction is closely related to the individual comorbidities profile.

All-Arthroscopic Hydrogel-Based Autologous Chondrocyte Transplantation in the Knee Joint: Good Clinical and Magnetic Resonance Imaging Outcome After 24 Months

PURPOSE

To evaluate subjective and objective clinical and magnetic resonance imaging-based radiologic outcomes after short-term follow-up in patients with focal full-size cartilage lesions of the knee joint treated with all-arthroscopic hydrogel-based autologous chondrocyte transplantation.

METHODS

A retrospective study on patients with isolated focal cartilage defects of the knee joint who were treated with arthroscopically conducted matrix-induced autologous chondrocyte transplantation was performed. Clinical scores were assessed at baseline and final follow-up using the Tegner Score, visual analog scale, the International Knee Documentation Committee, and the 5 subscales of the Knee Injury and Osteoarthritis Outcome Score. Magnetic resonance imaging scans of the treated knee joints were evaluated with the updated MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) 2.0 scoring system at follow-up.

RESULTS

Twenty-nine consecutive patients were included in the study. Mean time to follow-up was 24.9 ± 1.1 months. Average visual analog scale decreased significantly from 6.5 ± 3.1 preoperatively to 2.3 ± 1.6 at follow-up (P < .0001). Tegner score increased from 3.1 ± 1.3 to 4.3 ± 1.2 (P < .0001) and the International Knee Documentation Committee from 43.8 ± 21.9 to 64.9 ± 18.9 (P < .0001). Also, all Knee Injury and Osteoarthritis Outcome Score subscales displayed significant improvements. Patients showed similar improvements of nearly all clinical scores independent of the defect size. Average MOCART2.0 score was 70.0 ± 13.6 and 20 patients scored ≥70 points. All 8 patients with large defects (>5 cm²) scored ≥75 points.

CONCLUSIONS

In this small study, injectable matrix-induced autologous chondrocyte transplantation therapy in the knee joint led to favourable clinical and radiologic short-term results with significant improvements in all clinical scores and MOCART2.0 scores, confirming morphologic integrity of the transplanted chondrocytes. Therefore, this minimally invasive procedure represents a promising operative technique for cartilage regeneration, even for large-diameter lesions.

LEVEL OF EVIDENCE

IV, therapeutic case series.

[Readmission rates of back pain patients after primarily conservative inpatient treatment at a university hospital]

Hintergrund

Die Patientenzahlen stationärer Versorgung von Rückenschmerzen steigen zunehmend, da die aktuellen Strukturen der ambulanten Versorgung den Bedarf nicht adäquat decken können. Die Infrastruktur des Maximalversorgers sichert zwar einerseits eventuelle Notfallversorgungen und bildgebende Verfahren ab, ist aber andererseits nicht auf die Ersatzleistung für die ambulante Versorgung ausgerichtet.

Ziel der Arbeit

Analyse der Wiederaufnahmeraten stationär primär konservativ versorgter Rückenschmerzpatienten.

Material und Methode

In der retrospektiven Studie wurde an einer universitären orthopädischen Klinik die Wiederaufnahmerate von Rückenschmerzpatienten innerhalb von 6 Monaten untersucht, die notfallmäßig stationär eingewiesen und dort primär konservativ behandelt wurden. Der Untersuchungszeitraum betrug 2 Jahre mit einer Nachbeobachtung von 6 Monaten. Es erfolgte die Auswertung von 413 Patienten.

Ergebnisse

Nach primär konservativer stationärer Therapie wurden 17,9 % der Patienten erneut stationär aufgenommen. Bis zur ersten Wiederaufnahme dauerte es 25 (±33,25) Tage und bis zur zweiten weitere 25,9 (±31,99) Tage. Rentner werden signifikant häufiger stationär aufgenommen, und in der Regel konservativ behandelt. 66,8 % der Vorstellungen erfolgten notfallmäßig ohne Einweisungsschein.

Diskussion

Die Wiederaufnahmen nach primärer konservativer stationärer Therapie sind relativ hoch. Bei straffem Management mit zügigem diagnostischem Vorgehen und zielgerichteten Nachbehandlungsstrategien kann die Rückführung des Patienten in die ambulante Versorgung in den meisten Fällen realisiert werden. Wiederaufnahmen erfolgen zur operativen Versorgung, oder aber ungeplant bei gescheiterter konservativer, ambulanter Therapie.

Subscapularis Tendon Tears - Usefulness of Written MRI Reports for Guiding Patient Referral to Shoulder Specialists

INTRODUCTION

 Rotator cuff tears are one of the most common reasons for shoulder pain, and patients often present initially to general practitioners. However, subscapularis tears are especially difficult to diagnose and hence adequate therapy is often delayed. General practitioners or non-specialist orthopedic surgeons need reliable MRI findings to allow timely referral of patients to shoulder specialists. The purpose of this study was to determine the validity of the written MRI report of patients with arthroscopically proven subscapularis tendon tears.

METHOD

 In this retrospective study, 97 patients (mean age 62.4 ± 10 years, 63 men) who underwent arthroscopic subscapularis repair between April 2013 and January 2015 by two experienced shoulder surgeons and who underwent a preoperative 1.5 T MRI study were included. All of these patients had high-field strength (i. e., ≥ 1.5 T) standard MRI scans performed within 4-164 (mean 57.4 ± 38.4) days before their arthroscopic procedures.

RESULTS AND CONCLUSION

 Subscapularis tendon tears, verified by arthroscopy, were correctly identified in only 37 of 97 cases in the written report of the preoperative MRI. This resulted in an overall low sensitivity of 38.1 %. Correctly predicted lesions were as follows: Fox and Romeo I 29.4 % (5/17 patients), Fox and Romeo II 20 % (7/35 patients), Fox and Romeo III 46.7 % (14/30 patients) and Fox and Romeo IV 73.3 % (11/15 patients). In contrast, concurrent supraspinatus tendon tears were identified correctly in 88.2 % of patients (60/68 cases, sensitivity 88.2 %, specificity 96.5 %). Preoperative written radiology reports provided by a heterogeneous group of 39 presumably non-MSK-specialized radiologic centers do not reliably detect subscapularis tendon tears and are not sufficient for guiding patients to specialist centers. Compared to other rotator cuff injuries, this study shows difficulties in the correct diagnosis of subscapular tendon injuries. However, this is necessary to provide patients with timely therapy. It can be assumed that MRI review by musculoskeletal-specialized radiologists would more often than not lead to the correct diagnosis.

KEY POINTS

  · Subscapularis tendon ruptures are difficult to diagnose on standard shoulder MRI.. · Written MRI reports from non-musculoskeletal-specialized radiologists are not reliable, especially for smaller lesions.. · Reliable findings are required for referral allocation to shoulder specialists (specialized musculoskeletal radiologists)..

CITATION FORMAT

· Lenz R, Kircher J, Schwalba K et al. Subscapularis Tendon Tears - Usefulness of Written MRI Reports for Guiding Patient Referral to Shoulder Specialists. Fortschr Röntgenstr 2021; 193: 797 - 803.

Predictors for an unsuccessful conservative treatment of patients with medial patellar plica syndrome

INTRODUCTION

In several cases persistent medial knee pain remains after conservative treatment in patients with medial patellar plica syndrome. In recent literature accepted criteria for surgical indication are lacking. In this retrospective study patients after conservative treatment were evaluated to identify predictors for an unsuccessful outcome.

MATERIALS AND METHODS

117 Patients with medial patellar plica syndrome between 2016 and 2019 were retrospectively evaluated. All patients received conservative treatment for three months. Surgery was indicated due to failed conservative treatment (n = 76) with persistent medial knee pain and restriction of activity after 3 months. Preoperative MRI analysis, Lysholm score, pain by the visual analog scale (VAS), postoperative sports participation (RTS) and Tegner activity score were collected at least 12 months after definite treatment. Statistical analysis was performed to evaluate differences between patients with successful and unsuccessful conservative treatment.

RESULTS

There were significant differences in the clinical and radiological findings between patients with successful and unsuccessful conservative treatment. Patients with failed conservative treatment showed a significant larger diameter of the medial patellar plica (0.8 ± 0.3 mm vs. 1.6 ± 0.4 mm; p < 0.05) and a significant higher rate of contact of the plica to the adjacent cartilage. Furthermore, these patients reported a significant higher rate of medial knee pain from flexion to extension and snapping symptoms. At final follow-up the patient-reported outcome by means of Lysholm score (96.25 vs. 95.93), RTS (96.2% vs. 97%) and Tegner activity score (6.0 vs. 6.01) was excellent after conservative and surgical treatment. There were no statistical differences in the preoperative and postoperative outcomes between both.

CONCLUSIONS

The diameter of a medial patellar plica and contact of the plica to the retropatellar cartilage as well as clinical signs like persistent medial knee pain from flexion to extension with snapping symptoms might be predictors for an unsuccessful conservative treatment and the need for surgical intervention in patients with painful medial patellar plica syndrome.

[Pitfalls due to manufacturer instructions in modern joint surgery]

Endoprosthetic implantations require the user to know numerous details of the installation process. Instructions from manufacturers are, therefore, always an essential part of legal proceedings in the event of premature implant failure. In addition to the application steps, the question of the application limits of the implants is also important. Patients' excessive safety expectations of the manufacturer or the medical user can also lead to avoidable product liability. Overall, there is a need to define standards and minimum requirements in package inserts and instructions, even if these can only be developed in accordance with the current state of science.

Hyperflexion Knee Injury with Anterior Cruciate Ligament Rupture and Avulsion Fractures of Both Posterior Meniscal Attachments: A Case Report

CASE

A 54-year-old patient presented with low-velocity hyperflexion knee trauma while falling at a ski lift with anterior cruciate ligament (ACL) rupture and avulsion fractures of both posterior meniscal attachments. Meniscal avulsions were treated arthroscopically using transtibial sutures; a partial medial collateral ligament tear was treated conservatively. Six weeks later, reconstruction of the ACL was performed, and both meniscal attachments were stable.

CONCLUSION

Hyperflexion of the knee puts direct shear and compressive force on the posterior tibia. This can result in ligament injuries combined with avulsion fractures of both posterior meniscal attachments. Arthroscopic treatment is a practicable technique for this type of injury.

Cost Analysis in Shoulder Surgery: A Systematic Review

BACKGROUND

Cost analysis studies in medicine were uncommon in the past, but with the rising importance of financial considerations, it has become increasingly important to use available resources most efficiently.

PURPOSE

To analyze the current state of cost-effectiveness analyses in shoulder surgery.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

A systematic review of the current literature was performed following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. All full economic analyses published since January 1, 2010 and including the terms "cost analysis" and "shoulder" were checked for usability. The methodological quality of the studies was assessed using the Oxford Centre for Evidence-Based Medicine levels of evidence and established health economic criteria (Quality of Health Economic Studies [QHES] instrument).

RESULTS

A total of 34 studies fulfilled the inclusion criteria. Compared with older studies, recent studies were of better quality: one level 1 study and eight level 2 studies were included. The mean QHES score was 87 of 100. The thematic focus of most studies (n = 13) was rotator cuff tears, with the main findings as follows: (1) magnetic resonance imaging is a cost-effective imaging strategy, (2) primary (arthroscopic) rotator cuff repair (RCR) with conversion to reverse total shoulder arthroplasty in case of failure is the most cost-effective strategy, (3) the platelet-rich plasma augmentation of RCR seems not to be cost-effective, and (4) the cost-effectiveness of double-row RCR remains unclear. Other studies included shoulder instability (n = 3), glenohumeral osteoarthritis (n = 3), proximal humeral fractures (n = 4), subacromial impingement (n = 4), and other shoulder conditions (n = 7).

CONCLUSION

Compared with prior studies, the quality of recently available studies has improved significantly. Current studies could help decision makers to appropriately and adequately allocate resources. The optimal use of financial resources will be of increasing importance to improve medical care for patients. However, further studies are still necessary.

Mechanisms of Acute Knee Injuries in Bouldering and Rock Climbing Athletes

BACKGROUND

There is limited insight into the mechanisms of knee injuries in rock climbing and bouldering in noncompetitive and competitive athletes.

PURPOSE

To examine the traumatic mechanisms of injury, demographics, distribution, and severity of knee injuries in affected athletes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

During a 4-year period, we performed a retrospective multicenter analysis of acute knee injuries in competitive and noncompetitive climbing athletes. Traumatic mechanisms were inquired and severity levels, therapies, and outcomes recorded with visual analog scale, Tegner, Lysholm, and climbing-specific outcome scores.

RESULTS

Within the observation period, 71 patients (35% competitive athletes, 65% noncompetitive athletes) with 77 independent acute knee injuries were recorded. Four trauma mechanisms were identified: high step (20.8%), drop knee (16.9%), heel hook (40.3%), and (ground) fall (22.1%). The leading structural damage was a medial meniscal tear (28.6%), found significantly more often in the noncompetitive group. A specific climbing injury is iliotibial band strain during the heel hook position. Most injuries resulted from indoor bouldering (46.8%). Surgical procedures were predominantly necessary in noncompetitive climbers. One year after the injury, the Tegner score was 5.9 ± 0.8 (mean ± SD; range, 3-7); the Lysholm score was 97 ± 4.8 (range, 74-100); and the climbing-specific outcome score was 4.8 ± 0.6 (range, 2-5).

CONCLUSION

Increased attention should be placed on the climber's knee, especially given the worldwide rise of indoor bouldering. Sport-specific awareness and training programs for noncompetitive and competitive climbing athletes to reduce knee injuries should be developed, and sports medical supervision is mandatory.

CREBBP and WDR 24 Identified as Candidate Genes for Quantitative Variation in Red-Brown Plumage Colouration in the Chicken

Plumage colouration in birds is important for a plethora of reasons, ranging from camouflage, sexual signalling, and species recognition. The genes underlying colour variation have been vital in understanding how genes can affect a phenotype. Multiple genes have been identified that affect plumage variation, but research has principally focused on major-effect genes (such as those causing albinism, barring, and the like), rather than the smaller effect modifier loci that more subtly influence colour. By utilising a domestic × wild advanced intercross with a combination of classical QTL mapping of red colouration as a quantitative trait and a targeted genetical genomics approach, we have identified five separate candidate genes (CREBBP, WDR24, ARL8A, PHLDA3, LAD1) that putatively influence quantitative variation in red-brown colouration in chickens. By treating colour as a quantitative rather than qualitative trait, we have identified both QTL and genes of small effect. Such small effect loci are potentially far more prevalent in wild populations, and can therefore potentially be highly relevant to colour evolution.

Evaluation of Rock Climbing Related Injuries in Older Athletes

INTRODUCTION

With the growing enthusiasm from people of all ages about rock climbing and bouldering, adaptions and medical conditions of the older athlete have become increasingly important. We aimed to analyze injury demographics, distribution, and severity for the older rock-climbing athlete.

METHODS

During a 3-y period, we performed a single-center injury surveillance in athletes ≥35 y of age presenting with rock climbing-related injuries or complaints. A standard questionnaire and examination protocol were conducted.

RESULTS

A total of 198 patients (age 44.2±7.1 [35-77] y) (mean±SD, with range) with 275 independent injuries were recorded. Ninety percent of all injuries affected the upper extremity, 6% the lower extremity, and 4% other body regions. The Union Internationale des Associations d'Alpinisme injury scores were 2.0±0.3 (1-4), and no fatalities occurred. Acute injuries were observed in 32% and overuse injuries in 68% of all injuries. Among the overuse injuries, 47% were classified as degenerative overuse conditions. Athlete age did not significantly correlate with the development of overuse injuries and UIAA injury score, but subgroup analysis showed a weak correlation of the climber age with the development of degenerative conditions (P<0.05). The leading diagnosis of degenerative conditions was subacromial impingement syndrome of the shoulder.

CONCLUSIONS

Compared to younger athletes, older rock climbers demonstrate a higher proportion of overuse injuries, especially degenerative conditions. Profound knowledge of climbing injuries patterns and conditions in older rock climbers is crucial to prevent injuries among all age groups and to decrease the number of degenerative injuries.

A Randomized Phase 2 Study of Erenumab for the Prevention of Episodic Migraine in Japanese Adults

Objective

A phase 2, double‐blind, placebo‐controlled study to evaluate the efficacy and safety of erenumab for the prevention of episodic migraine in Japanese patients was conducted.

Background

Previous global clinical studies have demonstrated the efficacy of erenumab in the prevention of migraine.

Methods

Patients were randomized to placebo or erenumab 28, 70, or 140 mg administered subcutaneously once per month for 6 months. The primary endpoint was change from baseline in mean monthly migraine days over months 4‐6 of the double‐blind treatment phase. Secondary endpoints included the proportion of patients achieving ≥50% reduction from baseline in mean monthly migraine days (≥50% response) and change from baseline in mean monthly acute migraine‐specific medication treatment days (MSMD) and mean Headache Impact Test (HIT‐6™) scores. Efficacy outcomes were also determined at months 1, 2, and 3.

Results

Four hundred and seventy five patients were randomized 2:1:2:2 to placebo and erenumab 28, 70, and 140 mg, respectively. Greater reductions in monthly migraine days were observed for erenumab vs placebo with differences of –1.25 (95% CI: –2.10 to –0.41; P = .004), –2.31 (95% CI: –3.00 to –1.62; P < .001), and –1.89 (95% CI: –2.58 to –1.20; P < .001) days for erenumab 28, 70, and 140 mg. The odds of having a ≥50% response were 3.2, 5.6, and 4.7 times greater for erenumab 28 mg (95% CI: 1.30‐7.88; P = .009), 70 mg (95% CI: 2.60‐12.06; P < .001), and 140 mg (95% CI: 2.24‐9.99; P < .001) than for placebo. Greater reductions from baseline in mean acute monthly MSMD were observed for erenumab vs placebo with differences of –1.07 (95% CI: –1.80 to –0.35; P = .004), –2.07 (95% CI: –2.66 to –1.49; P < .001), and –2.04 (95% CI: –2.63 to –1.45; P < .001) days for erenumab 28, 70, and 140 mg. Erenumab 70 and 140 mg also resulted in greater improvements in HIT‐6™ scores. The safety profile was similar across treatment groups. The most common adverse event was nasopharyngitis, which occurred in 29.4% of patients in the placebo group and 28.9%‐33.3% of patients in the erenumab groups.

Conclusion

Monthly subcutaneous injections of erenumab 70 mg demonstrated statistically significant and numerically maximal efficacy with a favorable safety profile, suggesting that erenumab is a potential new therapy for migraine prevention in Japan.

[What do orthopedic and trauma surgeons expect from radiologists when interpreting imaging of the elbow?]

CLINICAL ISSUE

The elbow is a complex joint with a multitude of acute and chronic pathologies. In addition to the clinical examination, radiological diagnostics play a decisive role in the further therapeutic management.

DIAGNOSTIC WORK-UP/PERFORMANCE

While acute traumatic injuries often present with obvious structural changes and the need for rapid treatment decisions, chronic processes can present with less evident alterations. Especially in these cases there is a need for clear communication between the treating physician and the radiologist with respect to managing optimal imaging as the basis for a certain diagnosis and therefore optimal treatment. Basic prerequisites on both sides are detailed knowledge of all elbow pathologies, classifications and the spectrum of radiological diagnostic imaging.

ACHIEVEMENTS/PRACTICAL RECOMMENDATIONS

From the point of view of orthopedic surgeons the radiologist is responsible for the correct performance and interpretation of the necessary imaging procedures. The aim of this article is to give an overview of important aspects in the imaging of typical orthopedic/traumatic pathologies.

Erenumab in chronic migraine: Patient-reported outcomes in a randomized double-blind study

Objective

To determine the effect of erenumab, a human monoclonal antibody targeting the calcitonin gene-related peptide receptor, on health-related quality of life (HRQoL), headache impact, and disability in patients with chronic migraine (CM).

Methods

In this double-blind, placebo-controlled study, 667 adults with CM were randomized (3:2:2) to placebo or erenumab (70 or 140 mg monthly). Exploratory endpoints included migraine-specific HRQoL (Migraine-Specific Quality-of-Life Questionnaire [MSQ]), headache impact (Headache Impact Test–6 [HIT-6]), migraine-related disability (Migraine Disability Assessment [MIDAS] test), and pain interference (Patient-Reported Outcomes Measurement Information System [PROMIS] Pain Interference Scale short form 6b).

Results

Improvements were observed for all endpoints in both erenumab groups at month 3, with greater changes relative to placebo observed at month 1 for many outcomes. All 3 MSQ domains were improved from baseline with treatment differences for both doses exceeding minimally important differences established for MSQ–role function-restrictive (≥3.2) and MSQ–emotional functioning (≥7.5) and for MSQ–role function-preventive (≥4.5) for erenumab 140 mg. Changes from baseline in HIT-6 scores at month 3 were −5.6 for both doses vs −3.1 for placebo. MIDAS scores at month 3 improved by −19.4 days for 70 mg and −19.8 days for 140 mg vs −7.5 days for placebo. Individual-level minimally important difference was achieved by larger proportions of erenumab-treated participants than placebo for all MSQ domains and HIT-6. Lower proportions of erenumab-treated participants had MIDAS scores of severe (≥21) or very severe (≥41) or PROMIS scores ≥60 at month 3.

Conclusions

Erenumab-treated patients with CM experienced clinically relevant improvements across a broad range of patient-reported outcomes.

Clinicaltrials.gov identifier

NCT02066415.

Classification of evidence

This study provides Class II evidence that for patients with CM, erenumab treatment improves HRQoL, headache impact, and disability.

Efficacy and safety of erenumab (AMG334) in episodic migraine patients with prior preventive treatment failure: A subgroup analysis of a randomized, double-blind, placebo-controlled study

BACKGROUND

Erenumab was effective and well tolerated in a pivotal clinical trial of episodic migraine that included subjects both naïve to, and those who had failed, previous preventives. Here we evaluated the efficacy and safety of erenumab (70 mg or 140 mg) versus placebo in the subgroup of patients who had previously failed preventive treatment(s): ≥1 or ≥2 prior failed migraine preventive categories, and in patients who had never failed.

METHODS

Prespecified subgroup analyses evaluated change from baseline to months 4-6 (the primary endpoint of the blinded study phase) in monthly migraine days, achievement of ≥50% and ≥75% reduction in monthly migraine days, and change from baseline in acute migraine-specific medication days. Adverse events were also evaluated.

RESULTS

Treatment with both doses of erenumab resulted in greater reductions in monthly migraine days at months 4-6 (treatment difference versus placebo [95% CI], never failed subgroup: -0.9 [-1.5, -0.3] for 70 mg and -1.3 [-1.9, -0.7] for 140 mg; ≥1 prior failed medication categories subgroup: -2.0 [-2.8, -1.2] for 70 mg and -2.5 [-3.4, -1.7] for 140 mg; ≥2 prior failed medication categories subgroup: -1.3 [-2.6, 0.0] for 70 mg and -2.7 [-4.0, -1.4] for 140 mg). Similar results were observed in the monthly acute migraine-specific medication days endpoint, and in the achievement of ≥50% and ≥75% reduction in monthly migraine days. For the ≥50% reduction in monthly migraine day endpoint, placebo response in the no prior treatment failed group was 32.6%, in the ≥1 failed treatment 17.5%, and in the ≥2 failed treatments 11.1%.

CONCLUSION

Erenumab showed consistent efficacy in episodic migraine patients who had failed prior preventive treatments and was well tolerated across subgroups. The data suggest prior patients with prior treatment failures have lower placebo response rates.

Impact of compression stockings on leg swelling after arthroscopy - a prospective randomised pilot study

Background

Post-operative limb swelling may negatively affect the outcome of arthroscopic surgery and prolong rehabilitation. The aim of this pilot study was to evaluate the effect of compression stockings versus no compression on post-operative swelling and pain in the early post-operative phase.

Methods

A single-centre, randomised controlled trial was performed. Patients who underwent minor knee arthroscopy were randomised to wear class II compression stockings (23-32 mmHg) (CS) or no compression stockings (NCS) immediately post-operatively for ten days. All patients received low molecular weight heparin (LMWH) at prophylactic dosage. The primary outcome variable was post-operative swelling of the limb, quantified by using an optical 3D measurement system (Bodytronic© 600). Pain was rated on a visual analogue scale (VAS). From a total of 76 patients assessed, 19 patients were eligible for final analysis. The trial followed the CONSORT criteria, was registered at clinicaltrial.gov and approved by the local ethics committee.

Results

The circumference at the middle thigh (cF) was significantly different between groups at day 10 (p = 0.032; circumference − 1.35 ± 2.15% (CS) and + 0.79 ± 3.71% (NCS)). Significant differences were also noted around the knee (cD) at day 10 (p = 0.026) and a significant trend at cD and at the mid lower leg (cB1) at day 4. The volume of the thigh was also different with marked difference between days 1 and 4 between the two groups (p = 0.021; volume + 0.54 ± 2.03% (CS) and + 4.17 ± 4.67 (NCS)). Pain was lower in compression group (not statistically significant).

Conclusions

Post-operative limb swelling can be reduced significantly by wearing compression stockings in the early post-operative phase when compared to not wearing stockings. This may improve the rehabilitation process after arthroscopic surgery. The optimal duration of compression therapy seems to be between three and ten days.

Trial registration

clinicaltrials.gov (NCT02096562, date of registration 11.11.2013).

The Alzheimer's Prevention Initiative Generation Program: Evaluating CNP520 Efficacy in the Prevention of Alzheimer's Disease

Alzheimer's disease pathology begins decades before the onset of clinical symptoms. This provides an opportunity for interventional clinical trials to potentially delay or prevent the onset of cognitive impairment or dementia. CNP520 (a beta-site-amyloid precursor protein-cleaving enzyme inhibitor) is in clinical development for the treatment of preclinical Alzheimer's disease under the Alzheimer's Prevention Initiative Generation Program. The Alzheimer's Prevention Initiative is a public-private partnership intended to accelerate the evaluation of Alzheimer's disease prevention therapies. The Generation Program comprises two pivotal phase II/III studies with similar designs to assess the efficacy and safety of investigational treatments in a cognitively unimpaired population at increased risk for developing Alzheimer's disease based on age and apolipoprotein E (APOE) genotype (i.e., presence of the APOE ε4 allele). The program has been designed to maximize benefit to Alzheimer's disease research. Generation Study 1 (NCT02565511) and Generation Study 2 (NCT03131453) are currently enrolling; their key features are presented here.

Efficacy and safety of erenumab (AMG334) in chronic migraine patients with prior preventive treatment failure: A subgroup analysis of a randomized, double-blind, placebo-controlled study

Background

Erenumab was effective and well tolerated in a pivotal clinical trial of chronic migraine. Here, we evaluated efficacy and safety of monthly erenumab (70 mg or 140 mg) versus placebo in the subgroup of patients who had previously failed preventive treatment(s) (≥ 1, ≥ 2 prior failed medication categories) and in patients who had never failed.

Methods

Subgroup analyses evaluated change from baseline in monthly migraine days; achievement of ≥ 50% and ≥ 75% reduction in monthly migraine days; and change in monthly acute migraine-specific medication days. Adverse events were evaluated for each subgroup.

Results

Treatment with both doses of erenumab resulted in greater reductions in monthly migraine days (primary endpoint) at Month 3 (treatment difference [95% CI], never failed subgroup: −2.2 [−4.1, −0.3] for 70 mg and −0.5 [−2.4, 1.5] for 140 mg; ≥ 1 prior failed medication categories subgroup: −2.5 [−3.8, −1.2], for 70 mg and −3.3 [−4.6, −2.1] for 140 mg; ≥ 2 prior failed medication categories subgroup: −2.7 [−4.2, −1.2], for 70 mg and −4.3 [−5.8, −2.8] for 140 mg). Similar results were observed in the monthly acute migraine-specific medication days endpoint, and in the achievement of ≥ 50% and ≥ 75% reduction in monthly migraine days. There were no new or unexpected safety issues.

Conclusion

Erenumab showed consistent efficacy in chronic migraine patients who had failed prior preventive treatments and was well tolerated across subgroups.

Influence of Training of Orthopaedic Surgeons on Clinical Outcome after Total Hip Arthroplasty in a High Volume Endoprosthetic Centre

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.

Experiences with a Generator Tool for Building Clinical Application Modules

Objectives: To elaborate main system characteristics and relevant deployment experiences for the health information system (HIS) Orbis®/ OpenMed, which is in widespread use in Germany, Austria, and Switzerland.

Methods: In a deployment phase of 3 years in a 1.200 bed university hospital, where the system underwent significant improvements, the system’s functionality and its software design have been analyzed in detail. We focus on an integrated CASE tool for generating embedded clinical applications and for incremental system evolution. We present a participatory and iterative software engineering process developed for efficient utilization of such a tool.

Results: The system’s functionality is comparable to other commercial products’ functionality; its components are embedded in a vendor-specific application framework, and standard interfaces are being used for connecting subsystems. The integrated generator tool is a remarkable feature; it became a key factor of our project. Tool generated applications are workflow enabled and embedded into the overall data base schema. Rapid prototyping and iterative refinement are supported, so application modules can be adapted to the users’ work practice.

Conclusions: We consider tools supporting an iterative and participatory software engineering process highly relevant for health information system architects. The potential of a system to continuously evolve and to be effectively adapted to changing needs may be more important than sophisticated but hard-coded HIS functionality. More work will focus on HIS software design and on software engineering. Methods and tools are needed for quick and robust adaptation of systems to health care processes and changing requirements.

Intranet Meets Hospital Information Systems: The Solution to the Integration Problem?

Based on the results of an extensive market analysis and technology assessment, this paper summarizes the state of the art in web technology and compares it with the needs of integration in hospital information systems. Web technology and intranet have evolved to a core technology for distributed computing and distributed information systems. The advantage of platform independent distribution of information has led to euphoric visions of future integrated systems. However, true integration takes more than transparent access to heterogeneous information sources. To overcome the essential problems related to integration of autonomous systems it is important to find a common ontological basis for future component based systems.

Demand-driven Evolution of IT Systems in Healthcare

Objectives: To analyze and to optimize interdisciplinary clinical processes, to introduce an IT-supported model for demand-driven system evolution in healthcare, and to demonstrate the feasibility of the approach for a clinical example and to present an evaluation.

Methods: System evolution and change management are viewed as two sides of the same coin, thus formal methods for process analysis and IT system evolution were embedded into a goal-oriented change management model. Based on a process model, a Failure Mode and Effects Analysis (FMEA) and a computer simulation were performed. A tool for rapid application development (RAD) was used to incrementally improve the healthcare information system according to newly arising needs.

Results: Each of the formal methods used contributed to the successful reorganization of the interdisciplinary clinical process. An evaluation demonstrated significant improvements. An integrated IT application was implemented to support the optimized process.

Conclusions: Process improvement is feasible and effective when formal methods for process analysis and requirements specification are used in a reasonable and goal-oriented way. It might be necessary to trade off costs and benefits or simplify a given method in the context of a particular project. As the same information is utilized in different tools, it is supposed that the efforts for process analysis, documentation and implementation of adapted applications could be reduced if different tools were integrated and based on a single coherent reference model for description of clinical processes.

Impact of the patella height on the strain pattern of the medial patellofemoral ligament after reconstruction: a computer model-based study

PURPOSE

Medial patellofemoral ligament (MPFL) reconstruction is a key procedure for treating patellofemoral instability. However, controversy exists regarding the correct graft placement in different patellar heights. Therefore, our study aimed to investigate the influence of patellar height on MPFL insertion points.

METHODS

Strain patterns of the reconstructed MPFL were calculated using a dynamic musculoskeletal multibody simulation. Numerous patellar (proximal, central, distal) and femoral attachment sites (around the radiological point according to Schöttle) were analysed in the presence of different patella heights [Insall-Salvati (IS) indices 0.74, 1.0, 1.5] during dynamic knee flexion from 0° to 120°.

RESULTS

The reconstructed MPFL showed an almost isometric behaviour at the anatomic insertion (IS 1.0). Slight variation (<5 mm) around the ideal femoral insertion point resulted in only small changes in MPFL tension. However, a displacement of 10 mm led to a significant increase in MPFL tension, especially in the more anteriorly/proximally located femoral attachment points. Depending on the patella height, there exists an area of absolute isometry of the MPFL (length change <3 %) on the femoral condyle, which did not necessarily coincide exactly with the radiological point, but was located within a radius of 5 mm around it.

CONCLUSIONS

When reconstructed in the radiological femoral insertion point, MPFL strain patterns were only slightly affected by different patella heights (IS 0.74-1.5) suggesting that MPFL reconstruction could be safely performed using the radiological insertion. However, in case of a patella alta (IS 1.5), a slightly more proximal femoral insertion is beneficial for the biomechanical behaviour of the reconstructed MPFL.

Safety and efficacy of erenumab for preventive treatment of chronic migraine: a randomised, double-blind, placebo-controlled phase 2 trial

BACKGROUND

The calcitonin gene-related peptide (CGRP) pathway is important in migraine pathophysiology. We assessed the efficacy and safety of erenumab, a fully human monoclonal antibody against the CGRP receptor, in patients with chronic migraine.

METHODS

This was a phase 2, randomised, double-blind, placebo-controlled, multicentre study of erenumab for adults aged 18-65 years with chronic migraine, enrolled from 69 headache and clinical research centres in North America and Europe. Chronic migraine was defined as 15 or more headache days per month, of which eight or more were migraine days. Patients were randomly assigned (3:2:2) to subcutaneous placebo, erenumab 70 mg, or erenumab 140 mg, given every 4 weeks for 12 weeks. Randomisation was centrally executed using an interactive voice or web response system. Patients, study investigators, and study sponsor personnel were masked to treatment assignment. The primary endpoint was the change in monthly migraine days from baseline to the last 4 weeks of double-blind treatment (weeks 9-12). Safety endpoints were adverse events, clinical laboratory values, vital signs, and anti-erenumab antibodies. The efficacy analysis set included patients who received at least one dose of investigational product and completed at least one post-baseline monthly measurement. The safety analysis set included patients who received at least one dose of investigational product. The study is registered with ClinicalTrials.gov, number NCT02066415.

FINDINGS

From April 3, 2014, to Dec 4, 2015, 667 patients were randomly assigned to receive placebo (n=286), erenumab 70 mg (n=191), or erenumab 140 mg (n=190). Erenumab 70 mg and 140 mg reduced monthly migraine days versus placebo (both doses -6·6 days vs placebo -4·2 days; difference -2·5, 95% CI -3·5 to -1·4, p<0·0001). Adverse events were reported in 110 (39%) of 282 patients, 83 (44%) of 190 patients, and 88 (47%) of 188 patients in the placebo, 70 mg, and 140 mg groups, respectively. The most frequent adverse events were injection-site pain, upper respiratory tract infection, and nausea. Serious adverse events were reported by seven (2%), six (3%), and two (1%) patients, respectively; none were reported in more than one patient in any group or led to discontinuation. 11 patients in the 70 mg group and three in the 140 mg group had anti-erenumab binding antibodies; none had anti-erenumab neutralising antibodies. No clinically significant abnormalities in vital signs, laboratory results, or electrocardiogram findings were identified. Of 667 patients randomly assigned to treatment, 637 completed treatment. Four withdrew because of adverse events, two each in the placebo and 140 mg groups.

INTERPRETATION

In patients with chronic migraine, erenumab 70 mg and 140 mg reduced the number of monthly migraine days with a safety profile similar to placebo, providing evidence that erenumab could be a potential therapy for migraine prevention. Further research is needed to understand long-term efficacy and safety of erenumab, and the applicability of this study to real-world settings.

FUNDING

Amgen.

[Muscle, tendon and joint injections : What is the evidence?]

Injections at tendon insertions, in muscles and in joints are an important instrument in the conservative treatment of musculoskeletal diseases, for acute injuries as well as for chronic degenerative diseases. Local anesthetic agents and glucocorticoids are well-established medications; however, severe side effects, such as chondrolysis have sometimes been reported, particularly for local anesthetic agents. In addition platelet rich plasma (PRP) and hyaluronic acid are also widely used; however, the clinical effectiveness has not always been proven. This article gives an overview on the most commonly used medications for injections and the mechanisms of action. The indications for treatment and the evidence for the clinical adminstration of muscle, tendon and joint injections are described based on the currently available literature.

Safety and efficacy of AMG 334 for prevention of episodic migraine: a randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND

The calcitonin gene-related peptide (CGRP) pathway is a promising target for preventive therapies in patients with migraine. We assessed the safety and efficacy of AMG 334, a fully human monoclonal antibody against the CGRP receptor, for migraine prevention.

METHODS

In this multicentre, randomised, double-blind, placebo-controlled, phase 2 trial, patients aged 18-60 years with 4 to 14 migraine days per month were enrolled at 59 headache and clinical research centres in North America and Europe, and randomly assigned in a 3:2:2:2 ratio to monthly subcutaneous placebo, AMG 334 7 mg, AMG 334 21 mg, or AMG 334 70 mg using a sponsor-generated randomisation sequence centrally executed by an interactive voice response or interactive web response system. Study site personnel, patients, and the sponsor study personnel were masked to the treatment assignment. The primary endpoint was the change in monthly migraine days from baseline to the last 4 weeks of the 12-week double-blind treatment phase. The primary endpoint was calculated using the least squares mean at each timepoint from a generalised linear mixed-effect model for repeated measures. Safety endpoints were adverse events, clinical laboratory values, vital signs, and anti-AMG 334 antibodies. The study is registered with ClinicalTrials.gov, number NCT01952574. An open-label extension phase of up to 256 weeks is ongoing and will assess the long-term safety of AMG 334.

FINDINGS

From Aug 6, 2013, to June 30, 2014, 483 patients were randomly assigned to placebo (n=160), AMG 334 7 mg (n=108), AMG 334 21 mg (n=108), or AMG 334 70 mg (n=107). The mean change in monthly migraine days at week 12 was -3·4 (SE 0·4) days with AMG 334 70 mg versus -2·3 (0·3) days with placebo (difference -1·1 days [95% CI -2·1 to -0·2], p=0·021). The mean reductions in monthly migraine days with the 7 mg (-2·2 [SE 0·4]) and the 21 mg (-2·4 [0·4]) doses were not significantly different from that with placebo. Adverse events were recorded in 82 (54%) patients who received placebo, 54 (50%) patients in the AMG 334 7 mg group, 54 (51%) patients in the AMG 334 21 mg group, and 57 (54%) patients in the AMG 334 70 mg group. The most frequently reported adverse events were nasopharyngitis, fatigue, and headache. Serious adverse events were reported for one patient in the AMG 334 7 mg group (ruptured ovarian cyst) and one patient in the AMG 334 70 mg group (migraine and vertigo); these events were judged to be unrelated to AMG 334 treatment. Nine (3%) of 317 patients had neutralising antibodies. No apparent association was recorded between patients with positive anti-AMG 334 antibodies and adverse events. No clinically significant vital signs, laboratory, or electrocardiogram findings were recorded.

INTERPRETATION

These results suggest that AMG 334 70 mg might be a potential therapy for migraine prevention in patients with episodic migraine and support further investigation of AMG 334 in larger phase 3 trials.

FUNDING

Amgen.

Therapeutic Monoclonal Antibodies: What Headache Specialists Need to Know

BACKGROUND

Monoclonal antibodies (mAbs) are now an important part of the treatment armamentarium for a wide range of conditions including cancer, autoimmune diseases, inflammatory diseases of the joint and bowel, transplant rejection, and multiple sclerosis. Significant progress over the last 30 years in the development of therapeutic mAbs has resulted in improved efficacy and safety. Monoclonal antibodies approved for the treatment of neurological illnesses so far are limited to use in multiple sclerosis. Several therapeutic mAbs have completed phase 2 clinical trials for migraine prevention, and there are phase 3 trials underway for migraine prophylaxis and for cluster headache at the time of this writing.

AIM

The purpose of this review is to discuss the characteristics of mAbs, including their mechanism of action and safety profile, and briefly describe the mAbs being evaluated for the prevention of migraine and cluster headaches.

SUMMARY

Monoclonal antibodies have several features that distinguish them from small molecules, including very high selectivity, relatively long half-life that generally allows for once or twice monthly dosing, and significantly reduced potential for drug-drug interactions or other nontarget related toxicities. The clinical development of mAbs that target calcitonin gene-related peptide and its receptor is underway and will evaluate this promising new drug class for the prevention of migraine and cluster headache.

[Arthroscopic resection of the acromioclavicular joint]

OBJECTIVE

Arthroscopic resection of the painful and degenerative altered acromioclavicular (AC) joint without destabilization of the joint and therefore pain relief and improvement in function.

INDICATIONS

Conservative failed therapy of painful AC joint osteoarthritis. Impingement caused by caudal AC joint osteophytes. Lateral clavicular osteolysis.

CONTRAINDICATIONS

General contraindications (infection, local tumor, coagulation disorders), higher grade instability of the AC joint (resection only together with stabilization).

SURGICAL TECHNIQUE

Diagnostic glenohumeral arthroscopy. Treatment of accompanying lesions (subacromial impingement, rotator cuff, long head of biceps). Subacromial arthroscopy with bursectomy (partial) and visualization of the AC joint. Resection of caudal osteophytes. Localization of the anterior portal using a spinal needle in the outside-in technique. Resection of 2-3 mm of the acromial side and the 3-4 mm of the clavicular side with shaver/acromionizer.

RESULTS

An isolated open AC joint resection was performed in 9 studies and an arthroscopic resection in 6 studies. Good and very good results were obtained in 79% (range 54-100%) in open resection and 91% (range 85-100%) in arthroscopic resections. Patients were able to return to activities of daily life more quickly after arthroscopic resections than after open surgery.

Cell viability, collagen synthesis and cytokine expression in human osteoblasts following incubation with generated wear particles using different bone cements

In total hip arthroplasty, wear particles generated at articulating surfaces and interfaces between bone, cement and implants have a negative impact on osteoblasts, leading to osteolysis and implant loosening. The aim of this experimental study was to determine the effects of particulate wear debris generated at the interface between straight stainless steel hip stems (Exeter(®)) and three different bone cements (Palacos(®) R, Simplex™ P and Cemex(®) Genta) on cell viability, collagen synthesis and cytokine expression in human osteoblasts. Primary osteoblasts were treated with various concentrations of wear particles. The synthesis of procollagen type I and different cytokines was analysed, and markers for apoptosis and necrosis were also detected. The cytokine synthesis rates in the osteoblasts were initially increased and varied, depending on incubation time and particle concentration. Specific differences in the synthesis rates of interleukin (IL)‑6, IL-8, vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1) were observed with the different bone cements examined. The negative effect of the particles on the synthesis of procollagen type I and increased rates of cell apoptosis and necrosis were observed with all three cements analysed. Our present data suggest that wear particles from the interface between the total hip stem and bone cement have a significant effect on viability, cytokine expression and collagen synthesis in human osteoblasts, depending on the bone cement used.

Automatic Tuning of Spatially Varying Transfer Functions for Blood Vessel Visualization

Computed Tomography Angiography (CTA) is commonly used in clinical routine for diagnosing vascular diseases. The procedure involves the injection of a contrast agent into the blood stream to increase the contrast between the blood vessels and the surrounding tissue in the image data. CTA is often visualized with Direct Volume Rendering (DVR) where the enhanced image contrast is important for the construction of Transfer Functions (TFs). For increased efficiency, clinical routine heavily relies on preset TFs to simplify the creation of such visualizations for a physician. In practice, however, TF presets often do not yield optimal images due to variations in mixture concentration of contrast agent in the blood stream. In this paper we propose an automatic, optimization-based method that shifts TF presets to account for general deviations and local variations of the intensity of contrast enhanced blood vessels. Some of the advantages of this method are the following. It computationally automates large parts of a process that is currently performed manually. It performs the TF shift locally and can thus optimize larger portions of the image than is possible with manual interaction. The method is based on a well known vesselness descriptor in the definition of the optimization criterion. The performance of the method is illustrated by clinically relevant CT angiography datasets displaying both improved structural overviews of vessel trees and improved adaption to local variations of contrast concentration.

[Musculoskeletal modeling of the patellofemoral joint. Dynamic analysis of patellar tracking]

Numerical simulations contribute to the understanding of patellofemoral diseases. Whereas cadaveric studies are limited with respect to reproducibility of results, the impact of different operative approaches can be systematically evaluated based on mathematical models. The objective of this study was to introduce a musculoskeletal model which is capable of describing the dynamic interactions within the patellofemoral joint. It contains major bony and soft tissue structures of the right leg including the medial patellofemoral ligament (MPFL). Two operative approaches were considered based on the model to illustrate the effect on patellofemoral biomechanics during active knee flexion: On the one hand the effect of femoral insertion during MPFL reconstruction on medial soft tissue tension, and on the other hand the difference in patella kinematics before and after total knee arthroplasty. Finally, the potential of musculoskeletal models is discussed.

Titanium-copper-nitride coated spacers for two-stage revision of infected total hip endoprostheses

Within the first two years after total hip arthroplasty implant-associated infection has become the second most common reason for a revision surgery. Two-stage implant exchange is frequently conducted using temporary spacers made of antibiotic-loaded cement in order to prevent a bacterial colonization on the spacer. Avoiding several disadvantages of cement spacers, a conventional hemi-endoprosthesis was equipped with a copper-containing implant coating for inhibition of bacterial biofilms. In the present paper details of this novel treatment concept are presented including a case report.

Two-stage revision of implant-associated infections after total hip and knee arthroplasty

Septic loosening of total hip and knee endoprostheses gains an increasing proportion of revision arthroplasties. Operative revisions of infected endoprostheses are mentally and physically wearing for the patient, challenging for the surgeon and a significant economic burden for healthcare systems. In cases of early infection within the first three weeks after implantation a one-stage revision with leaving the implant in place is widely accepted. The recommendations for the management of late infections vary by far. One-stage revisions as well as two-stage or multiple revision schedules have been reported to be successful in over 90% of all cases for certain patient collectives. But implant associated infection still remains a severe complication. Moreover, the management of late endoprosthetic infection requires specific logistics, sufficient and standardized treatment protocol, qualified manpower as well as an efficient quality management. With regard to the literature and experience of specialized orthopaedic surgeons from several university and regional hospitals we modified a commonly used treatment protocol for two-stage revision of infected total hip and knee endoprostheses. In addition to the achievement of maximum survival rate of the revision implants an optimisation of the functional outcome of the affected artificial joint is aimed for.

[Biphosphonate-induced femoral stress fractures : A new problem and knowledge so far - case report]

During the last several years the treatment of osteoporosis with bisphosphonates has become accepted as a safe and effective procedure. However, recently there have been increasing numbers of reports of rare complications in the literature. Particularly the occurrence of atypical fractures of the femur has become a focus of interest but the problem is insufficiently known and only rarely addressed in the scientific discussion. The case illustrated here and a survey of the important facts in the recent literature highlight essential aspects of long-term bisphosphonate therapy.

369 EFFECT OF HOLDING TIME OF RAW HOLSTEIN FRIESIAN BULL EJACULATES BEFORE SEXING ON NON-RETURN RATES AFTER 56 DAYS

Flow cytometric seperation of X- and Y-chromosme-bearing sperm is the only reliable technique that has been used succesfully for commercialization of sexed semen in the dairy industry. However, sperm sexing results in lower fertility compared to conventional semen. Due to logistics like the distance between bull station and sorting laboratory, the number of flow cytometers, and the time needed for the sorting process itself, the holding time between ejaculation and freezing of sex-sorted semen is variable. This holding time could influence the fertility of sex-sorted semen. The aim of this study was to evaluate the effect of different holding times before sexing on the non-return rates on Day 56 post insemination (NRR56). Following collection, raw ejaculates were transported at room temperature (19°C) from two semen collection centers to the central sorting laboratory. Within 2-4 h after collection, volume, sperm concentration and quality of the ejaculates were determined. When accepted, aliquots of 1 mL of semen were stained every 45-60 min for 2 h. Subsequently, sexing was performed according to procedures described previously, using MoFlo SX™ sperm sorters (Garner DL and Seidel GE 2008 Theriogenology 69 : 886-895). Each aliquot of 1 mL semen was sorted for 45-60 min. Four flow sorters were used, so not more than 4 aliquots could be processed simultaneously. After sorting 3-4 h, semen was pooled and a charge number was assigned to this fraction of the ejaculate (called a freezerun). This procedure was done a maximum of 3 times. The time between collection of the raw ejaculate and freezing of the semen was 7-10 h for freezerun 1, 10-14 h for freezerun 2, and 13-18 h for freezerun 3. From September 2007 to April 2009, a total of 16,523 inseminations with sexed semen from 43 different Holstein bulls were performed for which non-return rates at 56 days (NRR 56) were recorded. There were no significant differences in NRR56 between the 3 freezeruns (t-test) (Table 1). The results shown in this study suggest that raw Holstein semen can be held at room temperature for up to 13-18 h prior to sexing and freezing without an effect on NRR56. This study did not indicate what the maximum holding time prior to sexing and freezing would be before resulting in a fertility decline. Table 1.Number of records and NRR56 for different freezeruns

Response of human osteoblasts exposed to wear particles generated at the interface of total hip stems and bone cement

Aseptic loosening of total hip replacement is mainly caused by wear particles. Abrasive wear occurs at articulating surfaces or as a consequence of micro-motions at the interface between femoral stem and bone cement. Direct impact of wear particles on osteolysis, the remodeling of the bone stock and a directly affected function of osteoblasts was described. The present study examined the response of human osteoblasts exposed to different wear particles, which were generated in a test device providing oscillating micro-motions at the interface between femoral stem and standard bone cement. Characterization of released particles was performed by quantifying the size distribution and the metal content of the wear debris. Human osteoblasts were incubated with particles obtained from hip stems with different material compositions (Ti-6Al-7Nb and Co-28Cr-6Mo) and rough and smooth surface finishings combined with standard bone cement (Palacos(R) R) containing zirconium oxide particles. Commercially pure titanium particles (cp-Ti) and particulate zirconium oxide (ZrO(2)) were used for comparative analyses. The results revealed significant (p < 0.05) reduction of the cell viability after exposure to higher concentration of metallic particles, particularly from Co-based alloys. In contrast, ZrO(2) alone showed significantly less adverse effects on the cells. When increasing metallic particle concentrations massive inhibition was also observed in the release of cytokines including interleukine-6 (IL-6) and interleukine-8 (IL-8), but the expression of Procollagen I and the cell viability showed the highest reduction after exposure to Co-based alloy particles from rough stems.