1st EFORT European Consensus "Medical & Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices": Background, Delphi Methodology & Consensus process.

The objectives of the 1st EFORT European Consensus on 'Medical and Scientific Research Requirements for the Clinical Introduction of Artificial Joint Arthroplasty Devices' were foremost to focus on patient safety by establishing performance requirements for medical devices. The 1st EFORT European Consensus applied an a priori-defined, modified Delphi methodology to produce unbiased, high-quality recommendation statements, confirmed by consensus voting of a European expert panel. Intended key outcomes are practical guidelines justified by the current stage of knowledge and based on a broad European Expert Consensus, to maintain innovation and optimisation of orthopaedic devices within the boundaries of MDR 2017/745. Twenty-one main research areas of relevance were defined relying on input from the EFORT IPSI WG1 'Introduction of Innovation' recommendations and a related survey. A modified Delphi approach with a preparatory literature review and work in small groups were used to prepare answers to the research questions in the form of 32 draft Consensus statements. A Consensus Conference in a hybrid format, on-site in the Carl Gustav Carus University of Dresden was organised to further refine the draft statements and define consensus within the complete group of participants by final voting, intended to further quantify expert opinion knowledge. The modified Delphi approach provides practical guidelines for hands-on orientation for orthopaedic surgeons, research institutes and laboratories, orthopaedic device manufacturers, patient representatives, Notified Bodies, National Institutes and authorities. For the first time, initiated by the EFORT IPSI (WG1 'Introduction of Innovation'), knowledge of all related stakeholders was combined in the 1st EFORT European Consensus to develop guidelines and result in a comprehensive set of recommendations.

Blood management in enhanced recovery after hip and knee replacement.

Enhanced recovery in orthopedic surgery is a global patient management strategy to achieve early functional recovery. Blood management is central to rehabilitation protocols after hip or knee replacement. Coagulation physiology in hip and knee replacement is now well described, showing aggravation of bleeding by hyperfibrinolysis. The present study approaches blood management via 3 questions. 1/How to anticipate and prevent transfusion risk preoperatively? Screening for predictive factors can target the at-risk population, enabling a strategy of preoperative hemoglobin level optimization. 2/How to improve intraoperative hemostasis so as to minimize blood loss? Anti-fibrinolytic and topical hemostatic agents have proven efficacy. Tranexamic acid plays a central role. The impact of the usual surgical techniques, such as pneumatic tourniquet and postoperative drainage, on bleeding needs assessment. 3/How to manage postoperative anemia? Anemia without signs of general intolerance is frequent at discharge, but has been little studied. This raises the question of the medical interest of correcting postoperative anemia. LEVEL OF EVIDENCE: Expert opinion, V.

Flexion gap stabilization by oversizing posterior condylar offset in deep-dished total knee replacement does not compromise flexion: A single-surgeon, retrospective, observational, mid-term series.

INTRODUCTION: In total knee replacement surgery, medio-lateral knee balancing is recognized as the key to achieving satisfactory functional results. But it may not be enough to stabilize the flexion gap using deep-dished implants. We achieved flexion gap balance by oversizing the femoral component, thus increasing the posterior condylar offset (PCO). The purpose of this study was to describe the applicability of this technique and to test whether it produced adverse effects on medium-term outcomes. We hypothesized that it would not compromise the results if used properly. We therefore asked: (1) at how many cases of flexion gap balance would require oversizing the femoral component; (2) if femoral components oversizing would modify the mid-term results as per forgotten joint score (FJS) scores and whether flexion gain would be comparable to patients in whom it was not increased. MATERIALS AND METHODS: Ninety-four patients (120 knees) were operated between September 2009 and 2011 (age 68±9 years) using the cementless Hyperflex version of the Natural Knees (Zimmer, Warsaw, IN, USA). Postero stabilization was achieved using deep-dished inserts. The Gender configuration has provided narrow inserts to better adapt the female anatomy. A special navigation system measured the displacement of the lateral and medial femoro-tibial contact points with infra-millimetric precision. Adopting a tibial cut first, gap-balancing technique with anterior referencing, the decision to oversize the femoral component relied on the 90° flexion drawer test, which showed more than 6mm sagittal laxity before the femoral bone cuts. Eighty-one (105 knees) patients were reviewed with average 63±27-month follow-up. RESULTS: Femoral components were augmented by 1 size in 60 cases and by 2 sizes in 7 cases. At final review, knees with an oversized femoral component (60) achieved the same results as those implanted with a non-oversized femoral component (n=45) in terms of mean flexion gain (-5°±34 versus -4°±23, p=0.78), mean FJS (63±26 versus 61±23; p=0.56). CONCLUSION: Balancing the Flexion gap by oversizing the femoral component did not compromise flexion range and functional results. LEVEL OF EVIDENCE: IV, Retrospective cohort study.

Patient selection does not improve the success rate of infected TKA one stage exchange.

BACKGROUND: One stage exchange of a chronically infected total knee arthroplasty (TKA) is recommended in selected cases only. However, there is little evidence regarding the usefulness of selection criteria. The goal of this retrospective study was to compare the results of two concomitant cohorts of patients with chronically infected TKA: one treated with a routine one-stage exchange (study group) and one treated with one-stage exchange in selected cases only (control group). The hypoyhesis tested was that the failure rate and repeat surgery rate were higher in the study group than in the control group. METHODS: One hundred and thirty one cases were selected: 54 in the study group and 77 in the control group. There were 63 men and 68 women with a mean age of 70years. All patients were followed up for a minimal period of time of two years or until death or recurrence of infection. RESULTS: Twenty five cases had a recurrence of infection: 9/54 in the study group and 16/77 in the control group (NS). The survival rate for being free of infection after four years was 85% in the study group and 78% in the control group (NS). The repeat surgery rate was significantly higher in the control group. CONCLUSION: The tested hypothesis was rejected. When one stage exchange is considered, patient selection does not improve outcome.

Outcome of arthroscopic treatment for displaced lateral clavicle fractures using a double button device.

PURPOSE: The purpose of this study was to assess the clinical and radiological outcomes of an arthroscopically assisted fixation of type IIB fractures using a double button device. METHODS: Twenty-one patients with a type IIB displaced fracture of the clavicle who received an arthroscopically assisted fixation using a double button device were enrolled from 2009 to 2011. Clinical assessment included the patient's demographics, cause of injury, delay before surgery, time for surgery, time before resuming work and sports, the Shoulder and Hand (QuickDASH) score, the Constant-Murley score and the visual pain analogue scale (VAS). Radiological examination consisted of anteroposterior and axillary radiographs. RESULTS: The median age of patients was 33 years (range 18-67). Mean follow-up was 35 ± 8.9 months (range 24-51 months). The average delay before surgery was 3 days (range 1-7). At final follow-up, the mean QuickDASH score, Constant score and VAS were respectively 3.2 ± 6 (range 0-25), 94.8 ± 9.9 (range 62-100) and 0.5 ± 1.2 (range 0-4). Seventeen (81 %) patients were able to resume work, including heavy manual labour, and to resume their sport activities as well. Postoperative complications included one transient adhesive capsulitis, a symptomatic acromioclavicular joint osteoarthritis and an implant failure with nonunion. Bony union was achieved in all other patients. CONCLUSION: This study has demonstrated that the arthroscopic treatment using a double button device was effective at providing a satisfactory functional outcome, minimizing the risk of complications and presenting low implant failure and low nonunion rates in patients with Neer type IIB fractures of the distal clavicle. Such results lead us to consider this minimally invasive technique as a first-choice treatment. LEVEL OF EVIDENCE: IV.

Arthroscopic double row cuff repair with suture-bridging and autologous conditioned plasma injection: Functional and structural results.

PURPOSE: The double row cuff repair with suture bridging is commonly used for arthroscopic rotator cuff repair (RCR). Despite its biomechanical qualities, the rate of iterative tears with this technique is important. The aim of our study was to evaluate the effect of autologous conditioned plasma (ACP) on functional results and on the rate of iterative tears after RCR by suture bridging. MATERIALS AND METHODS: A consecutive series of 65 patients who underwent arthroscopic double-row suture bridge (Speed-Bridge, Arthrex) primary cuff repair of symptomatic full-thickness supraspinatus tear (retraction <3 in the Patte classification) were evaluated. Mean patient age was 60 (+/-8). The supraspinatus was repaired by knot-less bridging (SwiveLock, Arthrex) with suture tape material. 2 homogenous groups were created (A: 33 patients, B: 32 patients). In group A, all patients received, besides the cuff repair, an intra-tendinous ACP injection. Constant scores and Simple Shoulder Tests (SST) were measured pre-operatively and after a minimum follow-up period of 12 months post-operatively. Structural integrity of the repairs was evaluated by MRI according to the Sugaya classification. Sugaya >4 were considered as iterative tears. RESULTS: Mean follow-up was 19 months (+/-42) in the 2 groups. The mean quantity of ACP injected was 6ml. (+/-1.5) and no specific complication of the injection was found. Mean preoperative Constant-Murley scores were 41,2 (±7,7) and 38 (±11)in group B. Mean normalized Constant-Murley score increased from 41 points (±7) pre-operatively to 70 points (±8) post-operatively in group A and from 38 points (±11) to 73 points (±11) in group B. There were no significative differences between the two groups (P > 0.05). In group A, 31 repairs were Sugaya 1-3 (94%), vs. 30 in group B (93%), and 1 was type 4 in group A (5%) vs. 2 in group B (8%). CONCLUSION: In both groups, RCR with suture bridging gave successful functional outcomes, with a low rate of iterative tear. In this preliminary study, the adjuvant effect of ACP injections could not be showed on both functional and structural results. Longer follow-up is needed to evaluate potential differences.

Visual impairment and hip fractures: a case-control study in elderly patients.

AIMS: To investigate the relationship between visual impairment and fall-related hip fracture and to determine the etiology of visual impairment in a population of elderly patients with hip fracture. METHODS: A case-control study compared 96 patients diagnosed with hip fracture to a randomly selected control group of 103 patients without hip fracture. Inclusion criteria for the case group were as follows: patients aged 60 years and over with a hip fracture. Clinical assessment included visual acuity and ophthalmic examination. RESULTS: Forty-three patients with hip fracture had a visual impairment compared to only 12 patients in the control group. Visual impairment was a significant risk factor for hip fracture (OR = 6.15; 95% CI 2.98-12.69). Twenty-seven hip fracture patients had an uncorrected refractive error compared to only 15 controls (OR = 2.78; 95% CI 0.92-8.35). There was no significant difference of dense cataract between both groups (OR = 2.28; 95% CI 0.75-6.93). Fourteen hip fracture patients had a macular degeneration compared to only 8 controls (OR = 5.63; 95% CI 1.57-20.18), and 10 patients had suspicion of glaucoma compared to only 5 controls (OR = 10.65; 95% CI 2.21-51.3). CONCLUSION: Visual impairment was significantly associated with an increased risk of hip fracture in elderly people. There are many etiologies that may contribute to hip fractures, most notably refractive error, cataract, macular degeneration and glaucoma.

Water absorption of poly(methyl methacrylate) measured by vertical interference microscopy.

PMMA (poly(methyl methacrylate)) is widely used to prepare orthopedic cements. They are in direct contact with cells and body fluids. PMMA, despite its hydrophobic nature, can absorb ~2% w/w water. We have evaluated by vertical interference microscopy if water absorption can produce a significant swelling in different types of PMMA blocks: pure, with a plasticizer, with a cross-linker, and in two types of commercial bone cements. Graphite rods which do not swell in water were used as internal standard. Hardness, indentation modulus, plastic, and elastic works were determined by nanoindentation under a 25mN fixed force. Vertical interference microscopy was used to image the polymer in the dry state and hydrated states (after 24 h in distilled water). On the surface of the polished polymers (before and after hydration), we measured roughness by the fractal dimension, the swelling in the vertical and the lateral directions. For each polymer block, four images were obtained and values were averaged. Comparison and standardization of the images in the dry and hydrated states were done with Matlab software. The average value measured on the graphite rod between the two images (dried and hydrated) was used for standardization of the images which were visualized in 3D. After grinding, a small retraction was noticeable between the surface of the rod and the polymers. A retraction ring was also visible around the graphite rod. After hydration, only the pure PMMA and bone cements had a significant swelling in the vertical direction. The presence of polymer beads in the cements limited the swelling in the lateral direction. Swelling parameters correlated with the nanoindentation data. PMMA can swell by absorbing a small amount of water and this induces a swelling that varies with the polymer composition and particle inclusions.

Less femorotibial rotation and AP translation in deep-dished total knee arthroplasty. An intraoperative kinematic study using navigation.

PURPOSE: Hyper-congruent inserts have been proposed as another means of posterior stabilization in total knee arthroplasty. Their kinematics, partially unexplored, is reported to be possibly erratic. The objectives of the present study were to detect whether prostheses with such a constrained design would provide antero-posterior (AP) stability without interfering with high flexion. METHODS: The kinematics of 10 knees replaced with hyper-congruent inserts was tested intra-operatively with a specially designed navigation system (Praxim, La Tronche, Isère, France), to measure AP displacements of femoro-tibial contact points at knee flexion. RESULTS: Femoro-tibial contact points in full extension were in a posterior position compared to their initial position before implantation (8 ± 6 mm medially, 15 ± 10 mm laterally, P < 0.004). AP displacements were different from pre-operative displacements (3 ± 4 mm vs -5 ± 2 mm for the medial condyle, P < 0.01 and -2 ± 6 mm vs -22 ± 8 mm for the lateral condyle, P < 0.001). Forward rolling persisted in four cases, with the medial condyle being involved in three of them (9, 9, and 6 mm, respectively). Post-operative flexion of 122° on average was not correlated with AP displacements. CONCLUSIONS: Hyper-congruent prostheses partially stabilized femoral condyles at knee flexion. Posterior displacements were reduced with no consequence on range of flexion. Posterior stabilization was imperfect, and paradoxical displacements were detected by navigation, which could therefore help optimize knee balance. LEVEL OF EVIDENCE: Diagnostic study, Level II.

Fixation failures of dual mobility cups: a mid-term study of 2601 hip replacements.

BACKGROUND: The use of dual-mobility cups has increased because of a low rate of dislocations combined with a 96% 15-year survival rate. However, late cup migrations have been attributed to their fixation (tripod - exact fit with two pegs and one extraacetabular screw) and the absence of porous coating. In a second-generation device, the designs were modified to achieve press-fit fixation and a layer of titanium beads was sintered on stainless steel cups. QUESTIONS/PURPOSES: We therefore (1) determined the midterm survival of press-fit, grit-blasted, second-generation cups with or without additional screws, compared with original tripod and (2) compared survival of grit-blasted dual-mobility cups with bimetallic porous-coated cups. METHODS: From a multiinstitutional trial, we reviewed 2408 patients with osteoarthritis implanted with 2601 prostheses of seven designs of a second-generation dual-mobility cup. The criteria for failure were migration, widening radiolucencies in any zone of the interface, or revision for cup loosening. The minimum followup was 5 years (mean, 7.7 years; range, 5-11 years). RESULTS: The 8-year survival rate of press-fit, grit-blasted cups was lower than that for press-fit, grit-blasted cups fixed with screws (91% versus 100%) and for tripod fixation (98%). The 8-year survival rate of press-fit, grit-blasted cups was less than that for press-fit, porous-coated cups made of the same alloy (91% versus 95%). CONCLUSIONS: The data suggested primary fixation of grit-blasted dual-mobility cups should be secured with screws. Porous coating sintered on the convex side improved midterm survivorship. No deleterious effect of metallosis resulted from sintered titanium beads on stainless steel. Long-term followup is required to confirm these findings.

Development of a phenotypic method for detection of fecal carriage of OXA-48-producing enterobacteriaceae after incidental detection from clinical specimen.

We report incidental isolation of an OXA-48-producing Escherichia coli strain in urine of a 62-year-old woman recently returning from a 2-month vacation in Morocco. Commercially available extended-spectrum beta-lactamase (ESBL)-targeting medium failed to detect it in the patient's stools, although a locally developed and easy-to-implement method using ertapenem-supplemented brain heart infusion (BHI) broths could.

Intra-operative navigation of knee kinematics and the influence of osteoarthritis.

Intra-operative assessment of knee kinematics should optimise implantation of total knee arthroplasties. The purpose of this work was to validate the data delivered by an adapted navigation system in 10 healthy cadaver knees and to investigate the kinematics of 10 osteoarthritic (OA) knees in patients undergoing total knee replacement. The system displayed the magnitude of axial rotation, the position of the instantaneous centre of axial rotation and the displacements of the condyles. Successive cycles from full extension to 140° of flexion in the same knee produced a mean external rotation of 20° ± 10°, which was correlated to knee flexion (r=0.6 ± 0.2 in healthy knees, r=0.8 ± 0.2 in OA knees). The centre of axial rotation migrated posteriorly an average of 8.2mm in both groups. The posterior displacements were 4 mm ± 5 mm in healthy and 5 mm ± 6 mm in OA knees for the medial condyle, and 21 mm ± 9 mm in healthy and 21 mm ± 10 mm in OA knees for the lateral condyle. The medial condyle lifted off beyond 110° of flexion. Results in healthy knees were consistent with those reported in the current literature. The kinematics of healthy and of OA knees with an intact anterior cruciate ligament did not differ significantly.

Long-term follow-up of 24.5 years after intra-articular anterior cruciate ligament reconstruction with lateral extra-articular augmentation.

BACKGROUND: Many studies have reported successful outcomes 10 to 15 years after ACL reconstruction. However, few authors report results at ultra long-term follow-up (more than 20 years of follow-up). PURPOSE: The aim of this study was to determine how the status of the medial meniscus and the medial compartment articular cartilage observed at the time of ACL reconstruction affects results more than 24 years after surgery. This article examines long-term outcome of ACL reconstruction with extra-articular augmentation (procedure performed through a medial arthrotomy). STUDY DESIGN: Case series; Level of evidence, 4. METHODS: One hundred of 148 patients reviewed at 11.5 years of follow-up could be reviewed at 24.5 years. Complete clinical and radiographic evaluation (International Knee Documentation Committee scale and Knee Injury and Osteoarthritis Outcome Score) was performed. RESULTS: The radiographic International Knee Documentation Committee rating was as follows: grade A, 39%; grade B, 7%; grade C, 27%; and grade D, 27%. Onset of osteoarthritis was correlated with medial meniscal status and femoral chondral defects at time of surgery. CONCLUSION: Total medial meniscectomy and articular cartilage damage were risk factors for osteoarthritis.

Extraspinal sciatica revealing late metastatic disease from parotid carcinoma.

Sciatica is a clinical symptom usually caused by a disk herniation and less often by other conditions such as tumors, infections, or inflammatory diseases. We report the case of a woman in whom sciatica led to the identification of a large pelvic metastasis from a carcinoma of the parotid gland.

Migration of wear debris of polyethylene depends on bone microarchitecture.

The mechanism of hip arthroplasties loosening is related to the migration of wear debris throughout the implant environment. In vivo, polyethylene particles (PE) were shown to infiltrate the bone implant interface and the medullary spaces of the cancellous bone. Our test hypothesis was that polyethylene particle migration is correlated to bone porosity. Bone samples with a high or low trabecular volume and microarchitecture were harvested in 20 calves and 20 human cadavers. They were extensively washed to remove marrow cells. Bone cylinders were filled with a light-curing monomer having the same viscosity as bone marrow. PE particles (7 and 33 microm) were deposited at the surface of the polymer. The bone cylinders were agitated during 7 days on an orbital shaker and the gel was left to polymerize at day light. X-ray microtomography was performed to characterize bone volume and microarchitecture. Cylinders were sectioned and observed under polarized light. The migration distance and rate were determined. Migration of PE particles strongly depended on trabecular bone volume and microarchitecture. We found a linear relationship (r = 0.61) between speed migration and bone volume and an exponential relationship between speed migration and bone architecture. The present in vitro model confirmed our hypothesis about the key role of bone microarchitecture in the migration of large PE wear particles. This is an explanation for the development of inflammatory reaction at distance from a prosthesis although our study did not include submicron particles.

Navigated revision knee arthroplasty using a system designed for primary surgery.

While navigation is now recognized as an efficient tool for improving femoro-tibial alignment of primary knee prostheses, its use in revision surgery has not yet been fully evaluated. We describe a procedure based on a bone morphing acquisition performed on the surface of the original implants, followed by a dependant bone cut sequence (tibia first). Using the current system, a preoperative CT-scan measurement of the original femoral component was required. Knee balancing was achieved using spacer blocks, with the trial tibial component and the original femoral component still in place. Preliminary experience from 19 cases, some with severe bone loss requiring reconstruction, is reported. A retrospective comparison to 10 non-navigated revision cases performed concomitantly by the same operating surgeon was carried out. Although there was no significant difference in the number of outliers for the two series, navigation appeared to be a valuable aid in reconstructing both bone extremities, while controlling the level of the joint line. However, definitive validation requires further prospective and comparative investigations in larger series.

Accuracy and reproducibility of computer-assisted measurement of polyethylene wear in knee arthroplasty.

When using computer-assisted methods to evaluate polyethylene wear in knee arthroplasty (TKA), variations in the inclination of the X-ray beam and lack of standard calibration may affect accuracy and reproducibility. To address these issues, we evaluated the polyethylene thickness of unimplanted specimens of known dimensions using the Imagika software. Radiographs were taken with small controlled variations in the inclination of the X-ray beam. Reproducibility was studied based on triplicate measurement of 132 fluoroscopic images by three observers. Calibration was tested against a reference based on a spherical metal ball with a known diameter. The mean differences between the measured and true values ranged from 0.6 mm to 0.8 mm. The repeatability coefficient revealed a maximum variation of 0.43 mm for the same observer, and 0.39 mm between observers. There were significant differences between the measurements of polyethylene thickness performed using two different calibration methods. The variance of measurements was lower with digitized images than with fluoroscopic images. Imagika was not efficient to measure wear in TKA.

[Acral myxoinflammatory fibroblastic sarcoma: a report of two cases]. / Sarcome fibroblastique myxoinflammatoire acral: à propos de deux cas.

Acral myxoinflammatory fibroblastic sarcoma is a rare low-grade malignant soft tissue tumor, usually observed in the extremities of middle-aged adults. We report two cases which occurred in the thumb and knee of middle-aged women. Both tumors showed a multinodular architecture, with cellular areas, occasional foci of hyalinized fibrosis, and hypocellular areas with a myxoid background. Various neoplastic cells were identified including spindled or rounded epithelioid cells and occasional bizarre giant cells, morphologically mimicking Reed-Sternberg cells or ganglion cells. Tumor cells were strongly immunoreactive for vimentin, and variably positive for CD68 and CD34. Both tumors were completely resected and patients were free of disease without any further treatment after a mean follow-up of 14 months.

Optimization of the posterior condylar offset, tibial slope, and condylar roll-back in total knee arthroplasty.

Total knee arthroplasty does not restore the full range of motion of the knee. Retrospective clinical studies on knee kinematics suffer from multiple biases because the various parameters involved, that is, the posterior condylar offset, the tibial slope, and the condylar roll-back, are not individualized. The present study, based on the geometry of knee flexion, shows that a 3-mm decrease of the posterior condylar offset could reduce knee flexion by 10 degrees before the occurrence of tibiofemoral impingement. In addition, the simultaneous decrease of the tibial slope by 5 degrees could reduce the flexion by a further 5 degrees. These effects could be reinforced if the paradoxical condylar roll-forward was made to exceed 10 mm. Finally, decreasing the condylar offset in a prosthesis with a paradoxical roll-forward and a neutral tibial slope could reduce maximum obtainable knee flexion before impingement by as much as 30 degrees.