bluuebunny/crossref_metadata_2025_split huggingface dataset:
Midterm Results Of Flanged Acetabular Cup Used In Severe Acetabular Defects
Authors: Pandey Arun Kumar 
Published: May 2020

Background: Revision hip arthroplasty complicated by massive acetabular defects and/or pelvic discontinuity has remained difficult to manage, with no definite option to produce predictable results. Acetabular cages and reinforcement rings have high failure rates because of lack of biological fixation. Custom triflange cups are economically demanding like cup-cage constructs, and require time to be fabricated. Cementless acetabular cup having an ischial hook and three iliac flanges is a technically simple but effective option to be used in such situations. Questions/purposes: We sought to determine (1) mid-term Kaplan-Meier survival; (2) clinical outcomes based on HSS and WOMACscores; (3) radiological outcomes based primarily on component migration; (5) mean operative time and (4) the complication rate for a series of 18 procedures. Methods: We conducted a retrospective review of all the revision hip arthroplasty procedures performed between January 2013 and May 2015 and identified 18 procedures in 18 patients where a cementless porous-coated hemispherical cup (Combicup-R, Link) was used. According to AAOS classification, 8 of the 18 (44%) acetabuli had Type 3 defect and 10 of 18 (56%) acetabuli had Type 4 defect. Structural bone allografts were used in 7 cases and all cases required morsellized allograft. The minimum followup was of 49 months and average was of 58 months (range, 49–67 months; SD, 34.3). Postoperative clinical evaluation was done at 6 weeks, 3, 6, and 12 months, and annually thereafter. HSS and WOMAC scores were recorded at follow up and radiographs were taken. Serial radiographs were compared with the 6-week postoperative radiographs to evaluate for component loosening/migration and structural graft resorption. Results: The 6-year Kaplan-Meier survival rate with revision for any cause representing failure was 93% (95% confidence interval [CI], 83.1–97.4). HSS and WOMAC score improved significantly from a preoperative value of 54 and 43 respectively to 87 and 85 postoperatively (p < 0.001). One patient had resorption of structural allograft and subsequent cup migration, which needed re- revision surgery. Conclusions: Porous coated acetabular cup supplemented with flanges and hooks is a suitable option to treat severe acetabular defects and pelvic discontinuity in acetabular revision reconstructions, than cages which do not provide biological fixation. Compared to custom triflange cups, they are more economical, technically easier to implant and do not require any waiting period to be fabricated.
A multicenter randomized controlled trial: matrix-augmented bone marrow stimulation with a polyglycolic acid membrane with hyaluronan vs. microfracture alone in local femoral cartilage defects of the femoral condyles
Authors: Glasbrenner Johannes , Petersen Wolf , Raschke Michael J. , Steiger Matthias , Castelli Claudio , Verdonk René , Fritschy Daniel , Herbort Mirco 
Published: May 2020

Aims and Objectives: Microfracture is the gold standard for the treatment of small localized chondral defects of the knee joint. There is evidence from animal studies that the augmentation of bone marrow stimulation by a matrix improves the quality of the repair tissue (matrix-augmented bone marrow stimulation = m-BMS). Aim of this randomized controlled trial was to examine the outcome of a matrix made of polyglycolic acid and hyaluronan in comparison to a conventional microfracture technique. Materials and Methods: In a randomized controlled trail (RCT) patients between 18-60 years with an articular femoral cartilage defect of 1-4 cm2 in the weight bearing area of the femoral condyles with indication for MF were enrolled and randomized to MF or m-BMS using a polyglycolic acid membrane with hyaluronan. Defect filling in MRI assessment at 12 weeks postoperatively was defined as primary outcome measure. MRI scans and follow up examinations including patient reported clinical outcome scores (VAS pain, KOOS, IKDC and SF-36) were performed at 12, 54 and 108 weeks after surgery. Results: There was no statistically significant difference between both groups in terms of defect filling assessed by MRI at 12, 54 and 108 weeks postoperatively. At 12 weeks there was a tendency towards higher degree of defect filling in the MF group when compared to the m-BMS group, whereas no difference was found after 54 and 108 weeks. The m-BMS group revealed superiority in terms of improvement over time in the KOOS subscales pain, knee-related symptoms, activity of daily living, sports and recreation and quality of life at 54 weeks and 108 weeks after treatment. Conclusion: This is the first RCT comparing m-BMS using a polyglycolic acid membrane with hyaluronan to any different treatment strategy in localized cartilage defects of any human joint. The use of the Chondrotissue® membrane in m-BMS of cartilage defects has proven to be a safe procedure with side effects comparable to those of MF. There seems to be an accelerated formation of cartilage repair tissue after MF when compared to m-BMS at 12 weeks postoperatively, whereas at one and two years after treatment there was no difference concerning the quantity of repair tissue. The improvement in clinical outcome scores over time after m-BMS might be due to the formation of cartilage repair tissue of higher quality. Long term follow up studies including histological assessment are desirable for further investigation.
Anteromedial instability of the knee
Authors: Wierer Guido , Milinkovic Danko , Robinson James , Weiler Andreas , Fink Christian , Raschke Michael J. , Herbort Mirco , Kittl Christoph 
Published: May 2020

Aims and Objectives: Anteromedial rotatory instability (AMRI) may result from combined lesions to the medial capsuloligamentous structures and anterior cruciate ligament (ACL). However, the contribution made by individual structures to controlling AMRI remains controversial. The purpose of the present study was to determine how the medial structures and ACL contribute to restraining simulated clinical laxity. Materials and Methods: Twenty-eight paired, fresh-frozen human cadaveric knees were tested in a six-degree of freedom robotic setup. After sequentially cutting the dMCL, sMCL, POL, and ACL in 4 different cutting orders, the following simulated laxity tests were applied at 0°, 30°, 60°, and 90° of knee flexion: 4 Nm external tibial rotation (ER), 4 Nm internal tibial rotation (IR), 8 Nm valgus rotation (VR) and anteromedial translation (AMT) - combined 89 N anterior tibial translation and 4 Nm ER. Knee kinematics (AMT, ER, IR, VR) were recorded in the intact state and after each cut using an optical tracking system. Differences in medial compartment translation and rotation from the intact state were then analyzed using Visual 3D. The kinematic data for each tested state, load, and flexion angle were analyzed using a 2-factor repeated-measures analysis of variance (ANOVA) and post-hoc Bonferroni corrections for multiple comparisons. Study Design: Controlled laboratory study. Results: The sMCL was the most important restraint to AMT (1.3 mm, 3.9 mm, 6.4 mm, 6.1 mm in 0°, 30°, 60°, 90°, respectively; P < 0.05), ER (1.8°, 4.4°, 6.3°, 5.3° in 0°, 30°, 60°, 90°, respectively; P < 0.01), and VR (4.1°, 4.8°, 5.8° in 30°, 60°, 90°, respectively; P < 0.05) at all flexion angles. Cutting the proximal tibial attachment of the sMCL caused no significant increase in laxity if the distal sMCL attachment remained intact. The dMCL was a minor restraint to AMT (1.3 mm, 1.8 mm, 1.6 mm in 0°, 30°, 60°, respectively; P < 0.05) and ER (1.5°, 1.2°, 1.1°, 1.0° in 0°, 30°, 60°, 90°; P < 0.05). The POL controlled IR near extension (3.3° in 0°; P < 0.05) and was a secondary restraint to AMT and ER in the ACL + MCL deficient knee. The ACL contributed in restraining AMT (4.0 mm, 6.2 mm, 4.2 mm, 3.0 mm in 0°, 30°, 60°, 90°, respectively; P < 0.01) and was a secondary restraint to ER and VR in the MCL deficient knee. Conclusion: The sMCL was the primary restraint to anterior subluxation of the medial tibial plateau, tibial ER and valgus rotation, which constitutes pathological laxity in AMRI. The dMCL and POL play a more minor role in restraining AMRI. Clinical Relevance: The simulated clinical tests (anteromedial drawer, external/internal rotation dial test and valgus stress test) allow determination of potential injury patterns causing AMRI. Based on the present data we propose a classification of anteromedial instability and suggest that for surgical treatment of AMRI it is important to address the sMCL.
Mobile bearing leads to less proximal medial tibial strain following UKA in comparison with fixed bearing in a cadaver setup
Authors: Heyse Thomas J. , Taylan Orcun , Slane Joshua , van Lenthe Harry , Peersman Geert , Scheys Lennart 
Published: May 2020

Aims and Objectives: Inexplicable pain to the medial proximal tibia is a frequent finding leading to revision after unicondylar knee arthroplasty (UKA). This study is an effort to find out, if there are any differences between mobile (MB) and fixed bearing (FB) UKA designs in terms of resulting strain in the medial proximal tibia as measured in an in vitro cadaver setup. It was hypothesized that MB UKA would result in lower bone strain. Materials and Methods: Five pairs of fresh-frozen full leg cadaver specimens were mounted in a kinematic rig that applied a dynamic squatting motion knee flexion after prior 3D CT. The rig allowed for 6 degrees-of-freedom at the knee while forces were applied to the quadriceps and hamstrings. During testing, an infrared camera system tracked the location of reflective markers attached to the tibia and femur with bicortical bone pins. Tibial cortical bone strain was measured with stacked strain gauge rosettes attached at predefined anterior and posterior positions on the medial cortex. Sensor outputs were recorded at 2000 Hz and synchronized with kinematic data prior and after pairwise implantation of MB and FB UKA directly comparing those between left and right knees from the same donor. Results: Bone strain values consistently increased with increasing flexion angle. FB UKA significantly increased strain in the anterior region of the medial tibial bone, while MB closely replicated strain values of the native knee. Conclusion: Proximal tibial bone strain seems to be lesser following MB UKA in comparison with FB UKA. Clinical studies will have to show, if this translates into a higher rate of pain problems with FB UKA.
3D-ANALYSIS OF LOWER LIMB ANATOMY: NORMAL VALUES FOR JOINT ANGLES AND ALIGNMENT
Authors: Fürmetz Julian , Sass Jan , Jalali Jalil , Degen Nikolaus , Böcker Wolfgang , Thaller Peter 
Published: May 2020

Aims and Objectives: The analysis of lower limb anatomy is mandatory in deformity surgery and total knee replacement. Standard values for joint angles and alignment are only available for 2D images using long standing and lateral radiographs. In contrast, 3D bone models realistically represent the anatomy and are independent of position and projection. Using a self-developed, standardised and validated protocol for 3D analysis of lower limb geometry, standard values for specific joint angles and axes can be obtained in a young cohort for the first time. Materials and Methods: After power and sample size analysis, 60 thin-slice CTs of the entire leg were analysed (30 patients, 13 f, 17 m; age = 33.8 [18-50 years]). After segmentation all 24 relevant bony landmarks were set using our standardised analysis method. Results of joint angles and mechanical axis deviation are calculated automatically. Mean values are stated with standard deviations to describe a possible reference range. Results: The mean neck-shaft angle (NSA) was 133±10° and the mean medial proximal femoral angle (MPFA) 85±9°. Around the knee joint, the mean mechanical lateral distal femoral angle (mLDFA) was 87±4° and the medial proximal tibial angle (MPTA) 88±5°. Medial and lateral slope averaged 12±7° and 9±8°. The deviation of the frontal mechanical leg axis from the knee joint center (MAD frontal) was 7±15mm and the mechanical femoro-tibial angle (HKA) 175±6°. Women showed a smaller mLDFA than men (86.4° vs. 87.8°, p<0.05) and a larger joint line convergence angle (JLCA 2.5° vs. 1.4°, p<0.01) representing a more valgiform anatomy. Conclusion: The standardised 3D analysis enabled reference ranges for the relevant joint angles and axes to be defined on the 3D bone model for the first time. The results redefine reference ranges for 3D measurements similar to existing 2D measurements on long standing radiographs. The systematic analysis of the complex 3D anatomy results in a multitude of new questions and possibilities in preoperative planning.
Long term results after ACL-reconstruction in childhood and adolescence
Authors: Zimmerer Alexander , Ellermann Andree 
Published: May 2020

Aims and Objectives: Ruptures of the anterior cruciate ligament in childhood and adolescence are severe injuries with increasing incidence over the last years. It is known today that the course of an unstable knee joint during growth can lead to poor subjective and objective results. The aim of the study is to record long-term results after transepiphyseal ACL reconstruction using autologous hamstring tendons and extracortical fixation in children and adolescents at least 15 years after surgery. Materials and Methods: We retrospectively evaluated patient who underwent ACL reconstruction in our clinic with arthroscopic transepiphyseal technique using hamstrings graft in childhood or adolescence with a follow-up of at least 15 years. In these patients, the Knee Injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Score (TAS), and Lysholm Score were collected, and clinical and MRI examinations were performed. Results: A total of 32 patients were identified, 5 of whom refused to participate. The average age at the time of surgery was 12 years, the average follow-up time was 17 years. In 3 patients a traumatic re-rupture was observed. None of the included patients showed a growth disorder at follow-up. The following subscores were found for the KOOS: KOOSpain 89, KOOSSymptom 82, KOOSADL 92, KOOSSport 75, KOOSQOL 82. The Tegner Activity score was 5.8, the Lysholm score 86 points. 13 of the 27 patients could also be examined clinically and by magnetic resonance imaging. In the MRI images, 95% of the patients showed intact grafts without evidence of cartilage or meniscus damage. The average lateral difference in the KT-1000 measurement was 1.5 mm. Conclusion: Transepiphyseal ACL reconstruction in children and adolescent with hamstrings is a save procedure leading to good long-term results. Secondary arthrosis signs can only be detected sporadically in MRI
Functional knee phenotypes - A novel classification for the lower limb alignment based on the native alignment in young non-osteoarthritic patients
Authors: Moser Lukas , Hess Silvan , Behrend Henrik , Hirschmann Michael 
Published: May 2020

Aims and Objectives: In total knee arthroplasty (TKA), the postoperative coronal alignment is a key factor for good clinical outcome. At the same time, the optimal alignment has been under debate recently. This debate usually focuses on the overall limb alignment while the details of the alignment, such as femoral or tibia alignment, are neglected. This might be partly because there is no concept which incorporates all parameters in a comprehensive and simple way. The purpose of this study was therefore to establish such a concept for the coronal knee alignment. Materials and Methods: The hospital registry was searched for patients older than 16 and younger than 45 years, who received a CT according to the Imperial Knee Protocol. Patients with prosthesis, osteoarthritis, fractures or injury of the collateral ligaments were excluded. Finally, 308 non-osteoarthritic knees of 160 patients remained (102 males and 58 females, mean age ± standard deviation (SD) 30±7 years). The following coronal alignment parameters were measured using a validated software (KneePLAN 3D, Symbios Orthopédie S.A): hip-knee-ankle angle (HKA, angle formed by the lines connecting the centers of the femoral head, the knee and the talus), femoral mechanical angle (FMA, angle between the mechanical axis of the femur and the tangent to the distal femoral condyles) and tibial mechanical angle (TMA, angle between the mechanical axis of the tibia and the tangent to the tibial plateau). Phenotypes for the limb, femur and tibia were defined based on these measurements. A phenotype thereby consists of a phenotype specific mean value (HKA, FMA or TMA value) and covers a range of ± 1.5° from this mean (e.g. 180°± 1.5). The phenotype specific mean values represent 3° increments of the angle starting from the rounded overall mean value of the angle. Results: Out of 125 possible phenotypes, 43 were found in these non-osteoarthritic knees (35 male, 26 female and 18 mutual phenotypes). The most common functional knee phenotype in males was NEUHKA0°NEUFMA0°NEUTMA0° (19%), followed by VARHKA3°NEUFMA0°VARTMA0° (8.2%). The most common phenotype in females was NEUHKA0°NEUFMA0°NEUTMA0° (17.7%), closely followed by NEUHKA0° NEUFMA0°VALTMA0° (16.6%). Conclusion: The functional knee phenotype concept better represents the variability of the coronal knee alignment than the conventional system of valgus, varus and neutral. Furthermore, it should enable a more detailed discussion about the coronal alignment and TKA alignment goals.
High Accuracy of Second Generation Unyvero ITI Automated Multiplex PCR Analysis of Joint Fluid Aspirate in Low-Grade Prosthetic Hip and Knee Joint Infections
Authors: Suren Christian , Feihl Susanne , Cabric Sabrina , Banke Ingo , Haller Bernhard , Trampuz Andrej , von Eisenhart-Rothe Rüdiger , Prodinger Peter Michael 
Published: May 2020

Aims and Objectives: A major obstacle for the treatment of prosthetic joint infections (PJIs) is the identification of the organism causing it. While the diagnostic criteria ruling PJIs in or out have become ever more accurate, detecting the causative pathogen(s) still relies mostly on conventional culture. The aim of this study was to evaluate the diagnostic potential of a second generation multiplex PCR assay (Unyvero ITI G2, Curetis AG, Holzgerlingen, Germany) used on synovial fluid specimens. Materials and Methods: Prospectively collected frozen joint fluid specimens from 26 patients undergoing arthroplasty revision surgery of the hip or knee for any reason were tested as per the manufacturer’s protocol. The sensitivity and specificity were calculated using the Chi-squared-test and a combination of the serum CRP level, leukocyte count, erythrocyte sedimentation rate, joint fluid culture, tissue biopsy culture, and tissue biopsy histology served as gold standard. Results: Of the 26 cases included in the study, 15 were infected and 11 aseptic. Conventional joint fluid culture showed a sensitivity 0.67 and a specificity of 0.91. Joint fluid multiplex PCR yielded a sensitivity of 0.8 and a specificity of 1.0. Conclusion: This is the first study to assess the second generation Unyvero ITI cartridge on joint fluid aspirate for the detection of prosthetic joint infection. In our setting, the method achieved a higher diagnostic accuracy than conventional culture. We conclude that, to improve pathogen detection before revision surgery, this method represents a valuable tool.
Arthrofibrosis of the knee: clinical result after early vs. late arthroscopic arthrolysis of 100 patients
Authors: Alm Lena , Klepsch Leonard , Akoto Ralph , Frosch Karl-Heinz 
Published: May 2020

Aims and Objectives: Distal femoral or tibial fractures as well as anterior cruciate ligament (ACL) tears can be associated with postoperative arthrofibrosis of the knee. So far, there are only a few studies that analyse this entity. The aim of the study is to evaluate potential risk factors that influence the outcome of patients with arthrofibrosis. We hypothesize that early arthroscopic arthrolysis is associated with a better postoperative outcome. Materials and Methods: 100 patients (at the time of the abstract submission n=59) with arthroscopic arthrolysis of postoperative arthrofibrosis of the knee were included in the retrospective study. They were clinically examined with a minimum follow-up of 2 years (mean 25±6 months). Arthrofibrosis was shown in 51% of the cases after ACL lesions, in 14% after femoral and tibial fractures, in 12% after infection and in 10% after patella fractures. The study population was divided into early (less than 3 months; n=19, mean 1.5 months) and late (more than 3 months; n=40, mean 8.7 months) arthroscopic arthrolysis after primary surgery. Results: In 51% of the cases (n=30) a normal range of motion could be postoperatively achieved (extension/flexion 0/140°). Patients with early arthroscopic arthrolysis showed significant more often a normal postoperative range of motion in comparison to patients with late revision (84% vs. 35%; p<0.001). Furthermore, patients with early arthrolysis had a significant lower postoperative flexion deficit than the late arthrolysis group (4° vs. 27°, p<0.001). The postoperative extension deficit was also significantly lower in the early arthrolysis group (0.4° vs. 3°; p=0,021). Postoperative functional scores were significantly higher after arthroscopic arthrolysis in comparison to before arthrolysis (Lysholm 85,1±11 vs. 41,3±9, p=0,049; Tegner 6,1±1 vs. 3,2±2, p=0,035; Cincinnati Rating Scale 83,1±13 vs. 52,1±16, p=0,046). Conclusion: Arthrofibrosis of the knee can be successfully treated with arthroscopic arthrolysis. Good postoperative results can be gained in treating flexion and extension deficits. Early arthroscopic arthrolysis shows significant better results in postoperative range of motion in comparison to late arthroscopic arthrolysis.