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Background The type of total knee arthroplasty (TKA) fixation (cemented or uncemented) is still subject to debate. The aim of this study is to assess the survival rate, clinical outcomes, and radiological results of TKA according to the fixation type. Methods A total of 130 patients were randomly assigned to either the cement group (cemented femoral and tibial implants) or the hybrid group (cemented tibial implant, uncemented femoral implant). The inclusion criteria were patients between 50 and 90 years old who underwent primary TKA for osteoarthritis between 2004 and 2005 without a history of open knee surgery. Revisions and complications were reported, as well as clinical scores and radiological signs of loosening. Results One hundred eighteen patients had complete data at 10 years of minimum follow-up (59 in each group). The mean age was 72 years old. The mean follow-up was 13 years. The survival rate was 98% at 13 years in both groups (1 aseptic loosening at 2 years in the cement group, 1 septic loosening in the hybrid group). The complication rate in the cement group was 8.5% (n = 5) vs 12.1% (n = 7) in the hybrid group (P = .8). The clinical results were not significantly different. In the cement group, 25% of patients (n = 15) had radiolucent lines at 10 years. In the hybrid group, 33% of patients had bone transparencies, not evolving or symptomatic. Conclusion At a minimum follow-up of 10 years, there were no significant differences between cemented TKA and hybrid TKA for the survivorship, the complication rate, the clinical scores, or the radiological signs of loosening. Level of Evidence I.

PURPOSE: Cup positioning is important for optimum hip stability, avoiding component impingement and decreasing both bearing surface wear and revision rate. Transitioning from posterior approach in a lateral position to direct anterior approach (DAA) in a supine presents unique challenges for surgeons. The aim of this study was to examine the learning curve when using standard instrumentation that was not specific to DAA. METHODS: A consecutive retrospective series of 537 total hip arthroplasty by DAA from May 2013 to December 2017. Cup positioning was analysed on radiographs and classified whether inside or outside two safe zones (inclination 30-50° and anteversion 10-30°). The demographic data (age, BMI, gender, neck shaft angle (NSA)), surgeon's dominant side and experience were assessed as risk factors. RESULTS: Eighty per cent of cups (n=426) were in the combined safe zones. Eighty-eight per cent (n=470) were in appropriate anteversion and 87% (n=463) abduction. Two factors that were significant were identified: Cups of left hips operated by right-handed surgeons were more anteverted (OR=4.06) and more vertical (OR=2.23); females had a higher anteversion of the cup (OR=2.42). Obesity, age and NSA were not risk factors for cup malposition. There was a spike of cups too horizontal at the beginning of the experience (OR=3.86), and no learning curve was observed in the other orientations. CONCLUSION: With our DAA technique using standard instrumentation, there were no risk factors linked to the patient identified for cup malposition. DAA-specific instrumentation is not required to achieve optimum positioning of the cup. Surgeon has to be aware of an excess of abduction at the beginning of his experience and an excess of anteversion and adduction when performing THA on the opposite side of his dominant hand.

The aim of this study was to evaluate the radiographic effect of sagittal tibial osteotomy (STO), flexion tibial osteotomy (FTO) and deflexion tibial osteotomy (DTO) around the knee. It has been hypothesized that proximal STO modifies patellar height and could cause varus/valgus changes of the anatomical tibial axis: The purpose of the study was to verify this and to analyse these modifications. Patients underwent proximal STO in our department between 2007 and 2018: overall 28 consecutive patients (19 males, 9 females; 28 knees). Twelve patients underwent DTO, and 16 patients underwent FTO. Two independent observers measured the pre-operative and post-operative radiological indexes: posterior tibial slope, Caton-Deschamps Index (CDI) and Modified Insall-Salvati Index (MISI) in the lateral views; medial Tibial Plateau-Tibial Shaft (mTPTS) and medial Femoral Shaft-Tibial Shaft (mFTA) anatomical angles were measured in the frontal plane. No complications were reported at the average follow-up of 1.6 ± 1.1 years. The mean mTPTS significantly increased from 0.6° ± 2.4° pre-operatively to 2.9° ± 2.6° of varus post-operatively (DTO (pre-operative 0.3 ± 3.1°, post-operative 2.4 ± 2.1°, ns); FTO (pre-operative 0.9 ± 1.9°, post-operative 3.2 ± 3.0°, P

Background: Arthroscopic anterior cruciate ligament (ACL) reconstruction (ACLR) with a bone–patellar tendon–bone graft (BTB) is a reliable surgical option for the control of anterior knee laxity after ACL injury. The addition of a lateral extra-articular tenodesis (LET) may improve control of rotation knee laxity and improve short-term graft survival in high-risk patients. Purpose: The aims of this study were to compare long-term patient-reported outcomes, graft survival, and risk of osteoarthritis between ACLR with and without LET. Study Design: Randomized controlled trial; Level of evidence, 2. Methods: This study included 121 consecutive knees (120 patients) presenting to a single center with an ACL rupture between 1998 and 1999. In total, 61 knees were randomized to an isolated BTB ACLR, and 60 knees were randomized to a BTB ACLR with an extra-articular lateral tenodesis with gracilis tendon (modified Lemaire). Results: Eighty knees in 79 patients (66%) were available for follow-up at a postoperative mean of 19.4 years (range, 19-20.2). Of those patients, 43 had a clinical examination and completed patient-reported outcome questionnaires, and the other 37 patients were evaluated through the questionnaires alone. Standard radiographs were available for 45 patients and laximetry (TELOS) for 42 patients. Mean subjective International Knee Documentation Committee score at last follow-up was 81.8, and no differences were noted between the BTB and BTB-LET groups ( P = .7). Two-thirds of patients were still participating in pivoting sports. A total of 17 knees (21%) experienced a graft failure, 5 of which (6%) underwent revision ACLR. There was no significant difference in graft failure risk between the BTB group (29%) and the BTB-LET group (13%; P = .1). Lateral tibiofemoral osteoarthritis was significantly more frequent in the BTB-LET group (59%) as compared with the BTB group (22%; P = .02). Lateral compartment osteoarthritis was correlated with partial lateral meniscectomy. Conclusion: There were no significant differences in long-term patient-reported outcomes after ACLR with or without an LET. LET may increase the risk of lateral compartment osteoarthritis at long-term follow-up. There was a trend toward decreased graft failure risk with the addition of LET but this study was underpowered to assess this outcome.

The purpose of this study was to compare the clinical results, radiographic loosening and early complications between patients undergoing primary knee arthroplasty (TKA) with tibial short stem extension and those with standard stem for gross varus deformities at minimum two years after surgery.From a prospective TKA database of 4216 patients, patients with a primary TKA with a tibial short stem extension (30 mm) for severe varus deformity (hip-kneeankle angle, HKA 170°) and a minimum follow-up of 2 years, were reviewed and compared to a matched control group with tibial components with a standard stem, in a 1:3 ratio. Demographics, surgical parameters, pre- and postoperative alignment and outcome parameters were collected for all patients. The primary outcome was aseptic loosening of the tibial component. Secondary outcomes were knee society scores (KSS), postoperative HKA, general postoperative complications and implant survival rates.Forty-five patients with tibial short stem extensions (mean HKA 166.2°) were compared in a 1:3 ratio to a matched case-control group of 135 patients with standard stems (mean HKA 167.1°) at a mean follow-up of 57 and 64 months respectively after primary TKA. In the extension stem group, 4 patients encountered complications (8.9%) versus 12 patients in the standard stem group (8.9%). There were no cases of tibial component loosening in the short extension stem versus four cases in the standard stem group (3%). This difference was significant between groups, p = 0.04.In patients with varus deformities 10°, undergoing primary total knee arthroplasty, prophylactic use of a tibial short extension stem may lead to less loosening of the tibial component. In this study, 3% of patient with big varus deformity without stemmed TKA had a tibial implant loosening versus 0% in the stemmed TKA group.Level III, case-control study.

Purpose: Meniscal lesions are commonly associated with anterior cruciate ligament (ACL) rupture. Meniscal repair, when possible, is widely accepted as the standard of care. Despite advancements in surgical and rehabilitation techniques, meniscal repair may impact muscle recovery when performed in conjunction with ACL reconstruction. The objective of this study was to explore if meniscal repairs in the context of ACL reconstruction affected muscle recovery compared to isolated ACL reconstruction. Methods: Fifty-nine patients with isolated ACL reconstruction were compared to 35 patients with ACL reconstruction with an associated meniscal repair. All ACL reconstructions were performed using hamstring grafts with screw-interference graft fixation. Isokinetic muscle testing was performed between six and eight months of follow-up. Muscle recovery between both groups was compared. A further subgroup analysis was performed to compare muscle recovery function of gender and meniscal tear location. Tegner scores were assessed at six months’ follow-up. Results: No significant differences were found between the two groups regarding muscle recovery. No difference in muscle recovery was found concerning gender. Lesion of both menisci significantly increased the deficit of hamstrings muscular strength at 60°/s compared to a lesion of one meniscus (26.7% ± 15.2 vs. 18.1% ± 13.5, p = 0.018) and in eccentric test (32.4% ± 26.2 vs. 18.1% ± 13.5, p = 0.040). No significant differences were found concerning the Tegner score. Conclusion: Meniscal repairs performed during an ACL reconstruction do not impact muscle recovery at 6–8 months post-operatively compared to an isolated ACL reconstruction. However, reparations of both menisci appear to impact hamstring muscle recovery negatively. Level of evidence: III, Retrospective cohort study

International audience; The Dual Mobility Cup (DMC) was created in 1974 to prevent dislocation and decrease wear. However, the movement of the polyethylene liner in vivo remains unclear. The aims of this study were to visualise liner positions and quantify the accuracy of the liner plane orientation for static positions, using ultrasound imaging. DMC reconstruction and angle between cup and liner were evaluated on isolated submerged DMCs by comparing 3D laser scans and ultrasound imaging. Moreover, the abduction and anteversion angles of the liner plane relative to the pelvis orientation were calculated via combined motion analysis and 3D ultrasound imaging on four fresh post-mortem human subjects with implanted DMC. On submerged DMC, the mean angle error between ultrasound imaging and 3D scan was 1.2°. In cadaveric experiments, intra-operator repeatability proved satisfactory, with low range value (lower than 2°) and standard deviation (lower than 1°). The study demonstrates the feasibility of measuring liner orientation on submerged and ex vivo experiments using ultrasound imaging, and is a first step towards in vivo analysis of DMC movement.

The purpose of the study was to determine the correlation between medial tibial slope (MTS) and anterior tibial translation (ATT) in female patients with an ACL-deficient knee. It was hypothesized that female patients with a greater medial tibial slope had an increased anterior tibial translation compared to males. MTS and ATT were analysed in 276 patients (138 females and 138 males) with a complete ACL rupture from 2012 to 2016. The mean age was 32 ± 12 years. Previous surgery or additional ligament injury was excluded. CT scan was used for measuring MTS. Meniscal findings were reported. Anterior tibial translation and side to side difference (SSD) were measured by bilateral Telos™ stress radiography with knee flexion of 20°. There was no significant difference in ATT between females (5.4 ± 3.9) and males (5.8 ± 4.2), nor was there a difference in MTS between females (9.8 ± 2.8) and males (9.8 ± 2.7). A positive correlation was found between MTS and ATT absolute (r = 0.35, p

There is a growing interest in the potentially deleterious impact of antibiotics on gut microbiota. Patients with bone and joint infection (BJI) require prolonged treatment that may impact significantly the gut microbiota. We collected samples from patients with BJI at baseline, end of antibiotics (EOT), and 2 weeks after antibiotic withdrawal (follow-up, FU) in a multicenter prospective cohort in France. Microbiota composition was determined by shotgun metagenomic sequencing. Fecal markers of gut permeability and inflammation as well as multi-drug-resistant bacteria (MDRB) and Clostridioides difficile carriage were assessed at each time point. Sixty-two patients were enrolled: 27 native BJI, 14 osteosynthesis-related BJI, and 21 prosthetic joint infections (PJI). At EOT, there was a significant loss of alpha-diversity that recovered at FU in patients with native BJI and PJI, but not in patients with osteosynthesis-related BJI. At EOT, we observed an increase of Proteobacteria and Bacteroidetes that partially recovered at FU. The principal component analysis (PCoA) of the Bray–Curtis distance showed a significant change of the gut microbiota at the end of treatment compared to baseline that only partially recover at FU. Microbiota composition at FU does not differ significantly at the genus level when comparing patients treated for 6 weeks vs. those treated for 12 weeks. The use of fluoroquinolones was not associated with a lower Shannon index at the end of treatment; however, the PCoA of the Bray–Curtis distance showed a significant change at EOT, compared to baseline, that fully recovered at FU. Levels of fecal neopterin were negatively correlated with the Shannon index along with the follow-up (r2 = 0.17; p < 0.0001). The PCoA analysis of the Bray–Curtis distance shows that patients with an elevated plasma level of C-reactive protein (≥5 mg/L) at EOT had a distinct gut microbial composition compared to others. MDRB and C. difficile acquisition at EOT and FU represented 20% (7/35) and 37.1% (13/35) of all MDRB/C. difficile-free patients at the beginning of the study, respectively. In patients with BJI, antibiotics altered the gut microbiota diversity and composition with only partial recovery, mucosal inflammation, and permeability and acquisition of MDRB carriage. Microbiome interventions should be explored in patients with BJI to address these issues.

Traditionally in total knee arthroplasty (TKA), a post-operative neutral alignment was the gold standard. This principle has been contested as functional outcomes were found to be inconsistent. Analysis of limb alignment in the non-osteoarthritic population reveals variations from neutral alignment and consideration of a personalized or patient-specific alignment in TKA is challenging previous concepts. The aim of this review was to clarify the variations of current personalized alignments and to report their results. Current personalized approaches of alignment reported are: kinematic, inverse kinematic, restricted kinematic, and functional. The principle of “kinematic alignment” is knee resurfacing with restitution of pre-arthritic anatomy. The aim is to resurface the femur maintaining the native femoral joint line obliquity. The flexion and extension gaps are balanced with the tibial resection. The principle of the “inverse kinematic alignment” is to resurface the tibia with similar medial and lateral bone resections in order to keep the native tibial joint line obliquity. Gap balancing is performed by adjusting the femoral resections. To avoid reproducing extreme anatomical alignments there is “restricted kinematic alignment” which is a compromise between mechanical alignment and true kinematic alignment with a defined safe zone of alignment. Finally, there is the concept of “functional alignment” which is an evolution of kinematic alignment as enabling technology has progressed. This is obtained by manipulating alignment, bone resections, soft tissue releases, and/or implant positioning with a robotic-assisted system to optimize TKA function for a patient’s specific alignment, bone morphology, and soft tissue envelope. The aim of personalizing alignment is to restore native knee kinematics and improve functional outcomes after TKA. A long-term follow-up remains crucial to assess both outcomes and implant survivorship of these current concepts.

Resume Introduction La survenue d’une metastase peri-acetabulaire (MPA) est un tournant evolutif de la maladie cancereuse en raison des douleurs invalidantes entrainant une forte alteration voire une perte totale de la marche. Les progres recents dans la maitrise des tumeurs primitives osteophiles et du controle local de la destruction osseuse justifient cette etude nationale. Les donnees en France sont mal connues ou portent sur des series limitees, aussi nous avons analyse une cohorte retrospective multicentrique de patients operes d’une MPA par arthroplastie totale de hanche afin d’evaluer : 1) le resultat clinique et radiologique; 2) les evenements impactant la survie des patients. Hypothese Le resultat clinique, le taux de complication et la survie etaient comparables a ceux de la litterature recente. Materiel et methodes Quatre-vingt-onze patients (27 hommes et 64 femmes) d’âge moyen 62,7 ± 10,5 ans (extremes 38 et 88) ont ete operes d’une MPA principalement secondaire a une tumeur mammaire (42 patientes (46 %)), ou broncho-pulmonaire (20 patients (22 %)). La metastase etait revelatrice 33 fois (36 %). Une atteinte viscerale concomitante etait presente chez 30 patients (33 %), osseuse peripherique multiple chez 48 patients (53 %) et rachidienne synchrone chez 39 patients (43 %). Le montage le plus habituel utilise une tige cimentee, avec un renfort acetabulaire metallique et une interface double mobilite 71 fois (78 %). Resultats Une suppression ou une diminution de la douleur ont ete rapportees pour 81 patients (91 %) et la fonction globale de la marche etait jugee normale ou acceptable pour 74 patients (83 %). Six deces (6,6 %) sont survenus avant la fin du 3e mois. Sept complications generales (7,7 %) dont 5 accidents thrombo-phlebitiques et 22 complications liees au geste operatoire pour 20 patients (21,9 %) ont necessite une reprise chirurgicale : 10 infections du site operatoire (10,9 %) et 3 luxations (3,3 %) ont ete deplorees. La mediane de survie toute etiologie confondue etait de 19,5 mois ; elle etait respectivement de 23,7 mois et 8,9 mois pour les MPA mammaires et broncho-pulmonaires. Conclusion Malgre des criteres d’evaluation differents, les resultats cliniques obtenus sont conformes a la litterature ; de meme les taux de complication du site operatoire et la survie. La technique chirurgicale recommandee est la pose d’un anneau de renfort, d’un curetage comblement par du ciment des zones osteolytiques, d’une interface double mobilite et d’une tige scellee suivie d’une radiotherapie. La place respective de l’arthroplastie et des gestes de radiologie interventionnelle reste a preciser. Niveau de preuve IV, Etude retrospective sans groupe controle.

45e Congrès de la Société de Biomécanique, Metz, France, 26-/10/2020 - 28/10/2020; Femoral fractures are a common issue for metastatic cancer patients. This type of fracture can occur during every day activities (Benca et al. 2017). Metastatic lesions can be osteoblastic, osteolytic or mixed but, mechanically, lytic lesions are more critical for the femoral strength (Benca et al. 2017). Based on a clinical scoring (Mirel's score), fracture predictions are overestimated and poorly predicted (Mirels 1989; Van der Linden et al. 2004; Benca et al. 2017), which leads to over-surgery. This scoring system is based on four following variables: metastases' site, size and type, and patient's pain (Mirels 1989). Hence, clinical studies do not focus on bone strength, but mainly on metastases characteristics and patient's pain. Finite element models, based on Quantitative Computed Tomography (QCT) imaging, were carried out to predict failure load (e.g., Kaneko et al. 2008; Tanck et al. 2009; Yosibash et al. 2014). In the context of metastatic bone, for a local validation, only one study has been published to study the major and minor principal strains using stereo-correlation (Sas et al. 2020) on cemented femur. The aim of this study was to provide experimental dataset to assess finite element models froma strain point of view.

PURPOSE: Very few studies focus on lateral unicompartmental arthroplasty (LUKA) in the setting of post-traumatic osteoarthritis (PTOA). The hypothesis of our study is that LUKA is an effective procedure for isolated lateral PTOA with similar outcomes to non-traumatic LUKA. METHODS: Between 1990 and 2016, eighteen LUKA performed for isolated lateral tibiofemoral osteoarthritis secondary to tibial plateau fracture were retrospectively reviewed (post-traumatic group) and matched with a control group of thirty-six LUKA performed for non-traumatic OA. Clinical (International Knee Score), radiological outcomes and revision rate were compared between the two groups with a minimum follow-up of three years. RESULTS: With a mean follow-up of 10.1years, postoperative IKS scores were similar between the two groups (IKS Knee: 89.1 (control) versus 85 (p=0.03) and IKS Function: 85.9 (control) versus 77.9 (n.s.). Clinical improvement was greater for the post-traumatic group. No difference was observed with regard to revision rate (3/18 (16.7%) cases in the post-traumatic group and 7/36 (19.4%) in the control group, n.s.) or polyethylene wear per year between the two groups. The revision free-survival rate was 64.8% for the post-traumatic group and 58.8% for the control group at 22-year follow-up (n.s.). CONCLUSION: LUKA is an effective procedure at long-term for patients suffering from isolated lateral PTOA with similar clinical and radiographic results compared to LUKA performed for non-traumatic OA and without increased risk of revision or prosthetic wear. LEVEL OF EVIDENCE: IV.

Purpose: The aim of this study was to perform a systematic review of the literature to determine whether there are any clinical or radiological differences in mechanically aligned Total Knee Arthroplasty (TKA) compared with kinematically aligned TKA.Methods: This study included retrospective cohort studies, prospective randomized controlled trials (PRCTs) and prospective cohort studies comparing clinical and radiological outcomes, and complications in TKA with kinematic alignment (KA) and mechanical alignment (MA). All studies had a minimum follow-up of 2 years.Results: Five PRCTs published between 2014 and 2020 were included. These studies showed a low risk of bias and were of very high quality. We did not find a superiority of KA compared to MA technique for clinical and radiological outcomes, except in one study which showed a significant difference favoring KA between the two groups for all clinical scores.Conclusion: We found that KA in TKA achieved clinical and radiological results similar to those of MA. The complication rate was not increased for KA TKAs. Studies with longer follow-up and larger cohorts are required to prove any benefit of KA technique over MA technique.

Introduction: Distal Femoral Osteotomy (DFO) is a common procedure for correcting lower limb valgus deformity and lateral compartment overload. Low 20-year survivorship rate was reported with a consequent need for total knee arthroplasty (TKA). This study aims to review literature and to analyse the influence of a previous distal femoral osteotomy on outcomes of patients undergoing TKA.Methods: A systematic literature review was performed in PubMed/Medline and Embase in May 2020. Papers were selected based on the following criteria: patient with a previous distal femoral osteotomy; total knee replacement; Pre- and Postoperative outcomes; surgical outcomes: clinical scores, range of motion, radiographic evaluation and revisions for any cause; case series, retrospective studies, observational studies, open-label studies, randomized clinical trials; systematic reviews and meta-analyses were included to extract primitive studies.Results: 306 articles were found, of which five papers were considered eligible for this review. In every study included, postoperative clinical outcomes (Knee Society Score or Hospital for Special Surgery score) statistically improved from the preoperative. Complications were not uncommon; implant survivorship at the available follow-up seems to be similar to primary TKA, although being too short to draw any conclusions.Conclusions: Limited and highly heterogeneous evidence is currently available on the influence of DFO on outcomes after TKA. Knee replacement improves clinical middle-term outcomes in patients with previous distal femoral osteotomy. In this complex surgery, the use of technical tips and tricks could help surgeons to obtain an accurate knee balancing and better long-term results.

Ultrasound assessment of the long head of the biceps (LHB) is difficult. The aim of the present study was to analyze the inter- and intra-observer reproducibility of 2 ultrasound cross-sections not previously assessed: humeral head apex (image 1) and bicipital groove entrance (image 2).These ultrasound cross-sectional images allow reliable and reproducible analysis of the intra-articular LHB.A single-center prospective study was conducted. Inter-observer reproducibility was assessed between 2 radiologists in 20 healthy shoulders (asymptomatic group) and 35 painful shoulders (symptomatic group); intra-observer reproducibility was assessed for 1 observer in 10 healthy shoulders. Quantitative parameters comprised short and long axes and transverse area, and qualitative parameters comprise echogenicity and LHB position.On images 1 and 2, inter-observer agreement on the 3 quantitative parameters was good to excellent in both subject groups (p0.05), and more precise and highly reproducible for image 1. Agreement on the 2 qualitative parameters was excellent (p0.001). Intra-observer reproducibility results were non-significant on all parameters.The 2 intra-articular LHB cross-sections proved reliable and reproducible in painful and in healthy shoulders. A standardized ultrasound protocol could thus enhance the precision of LHB assessment and treatment. The difficulties of LHB measurement, often related to shoulder pathology, may, however, hinder interpretation.III, prospective intra- and inter-observer study.

International audience; No abstract available

The aim of this study was to investigate the clinical and radiological results of the MAKO CT-based robotic-assisted system for total knee arthroplasty (TKA). A PRISMA systematic review was conducted using four databases (MEDLINE, EMBASE, Pubmed, GOOGLE SCHOLAR) to identify all clinical and radiological studies reporting information regarding the use and results of the CT-based robotic-assisted system to perform TKA between 2016 and 2020. The main investigated outcome criteria were postoperative pain, analgesia requirements, clinical scores, knee range of motion, implant positioning and the revision rate. The ROBINS-I tool (Risk Of Bias In Non-randomized Studies of Interventions) was used to evaluate the quality of included studies and the risk of bias. A total of 36 studies were identified, of which 26 met inclusion criteria. Of these 26 studies, 14 were comparative. The follow-up varied from 30 days to 17 months. This CT-based, saw cutting Robotic TKA is associated with a significantly lower postoperative pain score (2.6 versus 4.5) and with significantly reduced time to hospital discharge (77 h versus 105), compared with conventional TKA. The two comparative studies assessing functional outcomes at 1 year reported significantly better functional scores with CT-based robotic TKA compared with conventional TKA (WOMAC score: 6 ± 6 versus 9 ± 8 (p

Introduction: Proficiency in the direct anterior approach (DAA) as with many surgical techniques is considered to be challenging. Added to this is the controversy of the benefits of DAA compared to other total hip arthroplasty (THA) approaches. Our study aims to assess the influence of experience on learning curve and clinical results when transitioning from THA via posterior approach in a lateral position to DAA in a supine position. Methods: A consecutive retrospective series of 525 total hip arthroplasty of one senior and six junior surgeons was retrospectively analysed from May 2013 to December 2017. Clinical results were analysed and compared between the two groups and represented as a learning curve. Mean follow up was 36.2 months ± 11.8. Results: This study found a significant difference in complications between the senior and junior surgeons for operating time, infection rate, and lateral femoral cutaneous nerve (LFCN) neuropraxia. A trainee’s learning curve was an average of 10 DAA procedures before matching the senior surgeon. Of note, the early complications correlated with intraoperative fractures increased with experience in both groups. Operating time for the senior equalised after 70 cases. Dislocation rate and limb length discrepancy were excellent and did not show a learning curve between the two groups. Conclusion: DAA is a safe approach to implant a THA. There is a learning curve and initial supervision is recommended for both seniors and trainees. Level of evidence: Retrospective, consecutive case series; level IV.

Background:Reconstruction of the medial patellofemoral ligament (MPFL) is the gold standard treatment for recurrent patellar dislocation. Patella alta has been reported in about half of patients with recurrent patellofemoral instability.Hypothesis:MPFL reconstruction (MPFLr) has a beneficial role in the correction of patellar height in patients with mild patella alta (Caton-Deschamps index [CDI] between 1.20 and 1.40).Study Design:Case series; Level of evidence, 4.Methods:Skeletally mature patients, with no history of previous or concomitant knee surgical procedures, who underwent isolated MPFLr using hamstring autograft for recurrent patellar instability between 2005 and 2018, were included in this study. The authors calculated CDI, modified Insall-Salvati index (MISI), and Blackburne-Peel index (BPI) ratios. Measurements done by 2 independent observers were calculated and used to compare pre- and postoperative patellar height (patella alta: CDI >1.20).Results:A total of 89 patients (95 knees) were included in the study, with a mean age of 25.0 years (range, 15.0-45.0 years). There were 70% women and 30% men. We found patella alta in 35.8% of cases preoperatively. Among them, 79.4% had reduced patellar height indices, within normal limits, postoperatively (mean follow-up, 18.4 ± 12.0 months). All the ratios showed a significant reduction in patellar height after surgery (CDI: 0.19 [range, –0.05, 0.60]; MISI: 0.22 [–0.14, 0.76]; BPI: 0.18 [–0.08, 0.59]; P < .00001). The CDI of 79.4% of the study knees was reduced to within normal limits postoperatively. The CDI was maintained within normal limits postoperatively in 93.4% of the knees with normal patellar height and reduced to normal in 50% of the knees with severe patella alta before surgery . No patient reported patella infera before surgery, whereas this condition was found in 8.2% of study patients postoperatively. A moderate correlation was reported between preoperative radiographic indices and their reduction after surgery (CDI: P < .001, ρ = 0.39; MISI: P < .001, ρ = 0.39; BPI: P < .001, ρ = 0.48).Conclusion:The higher the preoperative patellar height, the more important is the lowering effect of MPFLr using the hamstring for patellar instability. Bony procedures should not be indicated in patients with patellar instability and a CDI between 1.20 and 1.40.

Background The use of piperacillin/tazobactam with vancomycin as empirical antimicrobial therapy (EAT) for prosthetic joint infection (PJI) has been associated with an increased risk of acute kidney injury (AKI), leading us to propose cefepime as an alternative since 2017 in our reference centre. Objectives To compare microbiological efficacy and tolerance of these two EAT strategies. Methods All adult patients with PJI empirically treated with vancomycin+cefepime (n = 89) were enrolled in a prospective observational study and matched with vancomycin+piperacillin/tazobactam-treated historical controls (n = 89) according to a propensity score including age, baseline renal function and concomitant use of other nephrotoxic agents. The two groups were compared using Kaplan–Meier curve analysis, and non-parametric tests regarding the proportion of efficacious empirical regimen and the incidence of empirical therapy-related adverse events (AE). Results Among 146 (82.0%) documented infections, the EAT was considered efficacious in 77 (98.7%) and 65 (98.5%) of the piperacillin/tazobactam- and cefepime-treated patients, respectively (P = 1.000). The rate of AE, particularly AKI, was significantly higher in the vancomycin+piperacillin/tazobactam group [n = 27 (30.3%) for all AE and 23 (25.8%) for AKI] compared with the vancomycin+cefepime [n = 13 (14.6%) and 6 (6.7%)] group (P = 0.019 and Conclusions Based on the susceptibility profile of bacterial isolates from included patients, microbiological efficacy of both strategies was expected to be similar, but vancomycin + cefepime was associated with a significantly lower incidence of AKI.

Lateral patellofemoral osteoarthritis is a relatively common condition in young, active patients. Partial lateral patellar facetectomy is a relatively minimally invasive option to restore knee function and return to sport when conservative treatments are insufficient. We describe the arthroscopic technique of partial lateral patellar facetectomy , which has been historically performed as an open procedure. We describe preoperative planning, arthroscopic portals, landmarks, intra-articular evaluation of bone resection, and surgical difficulties. The goal of the preoperative planning was a target bone resection of 10 to 15 mm including osteophytes and the lateral facet of the patella. Arthroscopic anterolateral and anterior superolateral portals were used to achieve the desired resection. An arthroscopic technique allows a direct view of the osteoarthritic bone for removal and permits intraoperative dynamic evaluation, which allows the surgeon to finetune the bone resection and obtain optimal patellar tracking. Avoiding arthrotomy could reduce morbidity and allows a rapid postoperative rehabilitation.

Introduction: Total knee arthroplasty (TKA) remains the treatment of choice for severe osteoarthritis of the knee and nearly 60% of patients undergoing TKA are women. Females present three notable anatomic differences. Thus, gender-specific (GS) components were introduced to accommodate the females’ anatomic differences. No systematic review has been published since 2014. The aim of this study was to perform a recent systematic review of the literature to determine whether there is any clinical benefit of gender-specific implants compared to conventional unisex implants in total knee arthroplasty (TKA).Methods: This study included prospective randomized controlled trials (PRCTs) comparing clinical and radiological outcomes, and complications in TKA with gender-specific implants and conventional implants. All studies had a minimum follow-up of two years.Results: Three PRCTs published between 2010 and 2012 were included. These studies showed a low risk of bias and were of very high quality. We did not find superior clinical outcomes for gender-specific prostheses compared to conventional prostheses. However, gender-specific TKA reduced the number of patients with femoral component overhang compared to conventional TKA.Conclusion: In our systematic review, despite a lower overhang rate, gender-specific implants in female TKA showed no clinical benefit over standard unisex implants. Good clinical results with significant improvement were observed with both designs. There is a notable absence of new studies on this subject in recent years, and further research needs to be performed using various gender-specific implant designs to further define the role of gender-specific implants.Level of evidence: Systematic review, Level IV

Introduction Isolated lateral compartment osteoarthritis of the knee (LCOA) is 10 times less frequent than medial compartment involvement. Long-term assessments of unicompartmental knee arthroplasty (UKA) in this indication are rare, with small series. Hypothesis Survival and functional outcome of lateral UKA in a large series are quite acceptable; the strategy is suited for isolated LCOA. Material and method A multicenter retrospective study in 6 French health establishments included all lateral UKAs performed between January 1988 and September 2014. Clinical data (range of motion, International Knee Society (IKS) knee and function scores, satisfaction), paraclinical data (radiologic angles) and complications were prospectively entered in medical files during follow-up and analyzed retrospectively at end of follow-up. Results During the study period, 311 lateral UKAs were performed in 295 patients, using 5 fixed-bearing implant models. Twenty-eight patients died within 5 years, and 15 (4.8%) were lost to follow-up. The series thus comprised 268 lateral UKAs in 63 male and 205 female patients, with a mean age of 68.8 ± 10.5 years, including 7 cases of post-traumatic osteoarthritis and 4 of aseptic osteonecrosis. Mean follow-up was 9.1 years (range, 5-23 years), implant survivorship with failure defined as all-cause revision surgery was 85.4% at 10 years and 79.4% at 20 years. At last follow-up, IKS knee score was 87.0 and IKS function score 80.2. Maximal flexion was 125°. 94.3% of patients were satisfied or very satisfied. The main cause of revision surgery was osteoarthritis in another knee compartment (66,7%, n = 26). Conclusion Lateral UKA showed good survivorship, comparable to medial UKA, with good functional results and excellent long-term satisfaction. Level of evidence IV, retrospective cohort study.

PURPOSE: The aim of this study was to compare the long-term clinical and radiological results between fixed (FB) and mobile bearing (MB) implants with identical design from the same manufacturer. METHODS: From March 2007 to May 2009, we recruited 160 patients in a prospective, single centered, randomized controlled trial. The authors compared 81 FB total knee arthroplasty (TKA) versus 79MB with medial compartment osteoarthritis. The same posterior stabilized HLS Noetos knee prosthesis (CORIN) was used in all patients. The two groups only differed by the tibial insert (fixed or mobile). The authors compared the postoperative Knee Society Score (KSS), the passive clinical and active radiological knee flexion, the implant survivorship, the complications, and the presence of radiolucent lines. RESULTS: At mean 10.5years' follow-up (range 8-12.1years) no significant differences were found in clinical scores (KSS (p=0.54), pain score (p=0.77), stair climbing (p=0.44), passive maximum flexion (p=0.5)) or for radiological analyses (maximum active radiological flexion (p=0.06), presence of progressive radiolucent lines (5 (MB group) versus 6 (FB group); p=0.75)) between groups. No significant difference was found in overall implant survivorship (82% (MB group) versus 78% (FB group) p=0.58) or complication rate (p=0.32) at the last follow-up. CONCLUSION: No significant clinical and radiological differences were found between fixed and mobile bearing TKA using the same semi-constrained implant type with comparable overall survivorship. The choice between a fixed or mobile bearing implant should be based on surgeon preference and experience with the selected implant. LEVEL OF EVIDENCE: Prospective randomized controlled trial, Level II.

Introduction: Preoperative anemia in patients undergoing a two-stage septic revision arthroplasty may be a factor of reinfection, even in the presence of aggressive antimicrobial therapy. Patient Blood Management (PBM) in such patients is challenging. We evaluate the impact of anemia existing before re-implantation on a failure rate after two-stage septic total knee arthroplasty (rTKA), and explore feasibility of a PBM strategy implementation in these patients. Materials and methods: A retrospective study of patients from January 2010 to January 2015 in a French regional referral center was performed. Patients undergoing a two-stage rTKA for infection after successful primary TKA were identified and followed up to 31.12.2018. The primary outcome (failure) was defined as surgical site infection after re-implantation requiring new surgery. The secondary outcomes were time to failure, the time between explantation/reimplantation, transfusion rate during the second stage. Preoperative anemia was defined as Hb level Results: 69 patients were identified; 17 (24%) developed reinfection of rTKA in 105 [11.4–156] days. In these patients pre-implantation anemia was more frequent (n = 13(76.5%) in failed vs. n = 21(40%) in non-failed, p = 0.0110). During the explantation stage, there were no significant group differences in age, sex, comorbidity, type of spacer and antimicrobial therapy, iron supplementation, or transfusion rate. The median time between explantation/reimplantation surgery was 51 [43–71.5] days, indifferent between the two groups. Intraoperative transfusion during reimplantation was required in 12 (17%) patients, more frequent in failed patients. None of the patients had contraindications for the PBM strategy except the cell-saver use. Conclusion: In two-stage septic rTKA preoperative anemia was almost two times more frequent and associated with an elevated rate of septic failure. The time-frame between explantation and-re-implantation is sufficient to implement a PBM strategy for all anemic patients. Before-after studies would be of interest to determine the best PBM strategy to prevent anemia-associated septic failure in such a condition.

PURPOSE: Many surgeons are performing total knee arthroplasty (TKA) with an aim to reproducing native anatomical coronal alignment. Yet, it remains unclear if primary osteoarthritic and non-osteoarthritic populations have similar knee coronal alignment. This study aims to describe and compare the distribution of femoral and tibial coronal alignment in a large primary osteoarthritic cohort and a young non-osteoarthritic cohort. METHODS: This is a retrospective analysis of a monocentric prospectively gathered data, from 1990 to 2019, of 2859 consecutive primary osteoarthritic knees in 2279 patients. Patients underwent standardized long-leg radiographs. Femoral mechanical angle (FMA) and tibial mechanical angle (TMA) were digitally measured using software. Femoral, tibial and knee phenotypes were analyzed, and descriptive data were reported. Data were compared to a young non-osteoarthritic population previously described. RESULTS: In osteoarthritic knees, the mean FMA was 91°±2.9° (range 86°-100°) and the mean TMA was 87°?±?3.1° (range 80°-94°). No significant difference was observed for FMA and TMA between genders. The most common femoral and tibial phenotypes were varus (38.7%) and neutral (37.1%). The most frequent knee phenotype was a varus femoral phenotype with a neutral tibial phenotype (15.5%), which is different to the non-osteoarthritic population. CONCLUSION: This study showed the wide distribution of knee phenotypes in a large osteoarthritic cohort. There was more varus distribution of the femoral coronal alignment compared to a non-osteoarthritic population, suggesting consideration and potential adaptation of the realignment strategy of the femoral component during TKA. LEVEL OF EVIDENCE: III.

International audience; No abstract available

Since its creation in 1974, the Dual Mobility Cup (DMC) has been gaining in popularity, especially in the past decade. This intensive use could lead to inappropriate use and consequently to an increased complication rate. Compliance with conceptual requirements and surgical techniques will prevent the occurrence of complications that can be wrongly attributed to implants. In this context, we feel that it is essential to share our tips and tricks as well as an overview and an explanation of common errors, based on more than 45 years of clinical and research experience. From basic principles, including indications, implant choice and implant compatibility, to surgical tips, in this article orthopedic surgeons will find a practical overview of DMC in order to use it safely and with confidence.

The hypotheses were that firstly there is few early specific complications due to the use of a robotic-assisted system for unicompartimental knee arthroplasty (UKA), and secondly there are less revisions and complications after robotic-assisted UKA than after conventional UKA. 200 robotic-assisted UKA (175 patients) and 191 conventional UKA (179 patients) were performed between 2013 and 2018 from the same center. Revisions, intraoperative and postoperative complications, functional and radiological results were collected at the most recent follow-up. At the most recent follow-up (≥ 1 year), revision rates were 4% (n = 8/200) for robotic-assisted UKA and 11% (n = 21/191) for conventional UKA (p = 0.014). Reoperation rates without implant removal were comparable in the robotic and conventional group (7.3% vs 8.6%). Complication rates for stiffness (4.7% vs 4.2%) and infection (1% vs 1.6%) were comparable in both groups. There was no specific complication related to the robotic-assisted system (no soft tissue or bone lesion caused by the use of the robotic-assistance and no complication related to the use of navigation pins). The KSS function scores were higher following robotic-assisted UKA (p = 0.01). Satisfaction rates and contralateral OA were comparable in the two groups. No complications due to the robotic-assisted system were found in this study. There was no difference in the general complications rate between both groups. Robotic-assisted UKA has a lower revision rate compared to conventional technique UKA at the short-term follow-up. III. This is the first paper comparing revision rate and clinical outcome between UKA performed using the NAVIO robotic system and a conventional technique and searching for specific complication related to the use of the NAVIO robotic system.

Introduction: Ceramic-on-ceramic couplings are an alternative bearing surface to reduce the problems related to polyethylene wear and debris. However, ceramic articulations have their own risk of unique complications: fracture, squeaking, or dislocation. Few studies have assessed the outcomes of ceramic-on-ceramic total hip arthroplasties (THA) by direct anterior approach (DAA). The aim was to evaluate the early complications and revision rate of ceramic-on-ceramic THA by DAA.Material: A retrospective single-center study of 116 consecutive THAs was performed by DAA (106 patients) with ceramic-on-ceramic bearing from January 2015 to February 2018 with a minimum 24 months of follow-up. No patients were lost to follow-up. The mean age was of 55.3 years ± 11.3. The same cementless acetabular shell with a Biolox Delta ceramic insert and head were used. The complication and revision rates were collected at the last follow-up. The positioning of the acetabular implant was assessed on standard radiographs. Postoperative clinical outcomes were assessed by the Harris Hip Score.Results: At a mean follow-up of 31.9 months ± 5.5, no THA was revised. Five patients had late complications: 3 squeaking (2.6%) and 2 psoas impingements (1.7%) and were managed conservatively. All patients had satisfactory bony ingrowth of acetabular component, with no radiolucent lines and no osteolysis. Eight patients (6.9%) had an anterior overhang of the cup. The mean overhang for these patients was 4.1 mm. 111 hips (96%) were perceived as forgotten or having no limitations.Conclusion: This ceramic-on-ceramic coupling and shell by DAA produced excellent clinical outcomes and implant survival rate at a minimum two-year follow-up study. No serious complication was observed during the follow-up.

Total knee arthroplasty (TKA) is an effective treatment for severe osteoarthritis. Despite good survival rates, up to 20% of TKA patients remain dissatisfied. Recently, promising new technologies have been developed in knee arthroplasty, and could improve the functional outcomes. The aim of this paper was to present some new technologies in TKA, their current concepts, their advantages, and limitations. The patient-specific instrumentations can allow an improvement of implant positioning and limb alignment, but no difference is found for functional outcomes. The customized implants are conceived to reproduce the native knee anatomy and to reproduce its biomechanics. The sensors have to aim to give objective data on ligaments balancing during TKA. Few studies are published on the results at mid-term of these two devices currently. The accelerometers are smart tools developed to improve the TKA alignment. Their benefits remain yet controversial. The robotic-assisted systems allow an accurate and reproducible bone preparation due to a robotic interface, with a 3D surgical planning, based on preoperative 3D imaging or not. This promising system, nevertheless, has some limits. The new technologies in TKA are very attractive and have constantly evolved. Nevertheless, some limitations persist and could be improved by artificial intelligence and predictive modeling.

Introduction: In patients undergoing a « debridement, antibiotics, and implant retention » (DAIR) procedure for acute staphylococcal prosthetic joint infection (PJI), post-operative treatment with rifampin has been associated with a higher probability of success.(1,2) However, it is not known whether it is the total dose, delay of introduction or length of therapy with rifampin that is most strongly associated with the observed improved outcomes. Methods: A multicentric, retrospective cohort study of patients with acute staphylococcal hip and knee PJI treated with DAIR between January 2011 and December 2016. Failure of the DAIR procedure was defined as persistent infection, need for another surgery or death. We fitted logistic and Cox regression multivariate models to identify predictors of DAIR failure. We compared Kaplan-Meier estimates of failure probability in different levels of the 3 variables of interest - total dose, delay of introduction or length of therapy with rifampin - with the log-rank test. Results: 79 patients included (median age 71 years [63.5-81]; 55 men [70%]), including 54 (68%) DAIR successes and 25 (32%) DAIR failures. Patients observed for a median of 435 days [IQR 107.5-834]. Median ASA score significantly lower in DAIR successes than in DAIR failures (2 vs. 3, respectively p = 0.011). Bacterial cultures revealed 65 (82.3%) S. aureus and 16 (20.3%) coagulase negative staphylococci, with 2 patients being infected simultaneously with S. aureus and CNS. Among S. aureus isolates, 7 (10.8%) resistant to methicillin; 2 (3.1 %) resistant to rifampin. Median duration of antimicrobial therapy was 85 days [IQR 28.5-97.8]. Fifty-eight patients (73.4%) received rifampin at a median dose of 14.6 mg/kg/day |IQR 13-16.7], started at a median delay of 8.5 days [IQR, 4-7.5] after debridement surgery. Twenty-one patients (26.6%) developed a drug-related adverse event, leading to rifampin interruption in 6 of them (7.6% of total cohort). Determinants of DAIR failure were rifampin use (HR 0.17, IC [0.06, 0.45], p-value

Patellar component positioning and patellofemoral kinematics are of great importance in total knee arthroplasty (TKA). The factors influencing patellar tilt are femoral rotation and lateral patellar release. However, the effect of patellar component size remains unknown. The aim of this study was to evaluate the intra-operative risk factors for patellar tilt, particularly the effect of the patellar component size. The hypothesis was that increasing the patellar component size would reduce the risk of patellar tilt. 878 primary TKAs with patellar resurfacing were included between January 2015 and October 2018. Analysis was performed at 1-year postoperatively on patients categorized into two groups: patellar tilt (PT) and no patellar tilt (NPT). A multivariate analysis was performed for the effect of patellar component size, femoral rotation, femoral overbuilding, patellar thickness and lateral release on patellar tilt risk. Secondary analysis was performed for any difference in clinical outcomes and revision rates between groups. Multivariate analysis showed that increasing the patellar component size decreased the risk of patellar tilt by 37% (p

International audience; Background: A consequence of the steady growth in the worldwide population of elderly individuals who remain in good health and continue to engage in sports is an increase in the incidence of anterior cruciate ligament (ACL) rupture occurring after 50 years of age. ACL reconstruction was formerly reserved for young athletes but now seems to produce good outcomes in over 50s. The type of graft and graft fixation method were selected empirically until now, given the absence of investigations into potential relationships of these two parameters with the outcomes. The objective of this study was to assess associations linking the type of graft and the method of femoral graft fixation to outcomes in patients older than 50 years at ACL reconstruction. Hypothesis: The operative technique is not associated with the clinical outcomes or differential laxity. Material and methods: A multicentre retrospective cohort of 398 patients operated between 1 January 2011 and 31 December 2015 and a multicentre prospective cohort of 228 patients operated between 1 January 2016 and 30 June 2017 were conducted. Mean follow-up was 42.7 months in the retrospective cohort and 14.2 months in the prospective cohort. The primary evaluation criterion was the clinical outcome as assessed using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Tegner Activity Score (TAS). Differential laxity was the secondary evaluation criterion. The Wilcoxon rank sum test and Kruskal-Wallis test were used to compare groups, and p-values < 0.05 were considered significant. Results: In the retrospective and prospective cohorts, hamstring tendons were used in 269 (67.6%) and 197 (86.4%) patients and extensor apparatus tendons in 124 (31.2%) and 31 (13.6%) patients. Femoral fixation in the retrospective cohort was cortical in 81 (20.4%) cases, by press-fit in 112 (28.1%) cases, and by interference screw in 205 (51.5%) cases; corresponding figures in the prospective cohort were 135 (59.2%), 17 (7.5%), and 76 (33.3%). The multivariate analysis of the retrospective data identified no significant associations of graft type or femoral fixation type with the KOOS, TAS, or differential laxity values. In the prospective cohort, hamstring grafts were associated with 0.6 mm of additional laxity (p = 0.007); compared to cortical fixation, press-fit fixation of patellar tendon grafts was associated with 0.3 mm of additional laxity (p = 0.029) and a 0.5-point lower TAS value (p = 0.033), with no difference in KOOS values. None of these differences were clinically significant. Discussion: The various ACL reconstruction techniques used in patients older than 50 years produce similar outcomes. The technique can be chosen based on surgeon preference without regard for patient age. Level of evidence: IV.

PURPOSE: Surgeons mainly consider the anterior anatomy of the distal femur in the treatment of patellar instability (PI) with trochlear dysplasia (TD). Through this research, the idea was to analyse the posterior femoral condyle length in TD. The research team posited the presence of morphological differences in the posterior part of the femoral epiphysis in TD compared to a control group. They also postulated that the posterior bicondylar angle (PCA), in the axial plane, was increased in TD. METHODS: This is a single-centre morphological study of 100 patients who had a computed tomography (CT) using the same protocol. 50 patients with PI (25 dysplasias A and 25 B-C-D according to the Dejour classification), and 50 controls were included. All patients presenting a clinical PI were considered for the study. None of these patients had undergone a surgical treatment prior to imaging. Demographic characteristics, BMI, and laterality were comparable in all patients. 20 pilot CT scans were used to establish the methodology. The following measurements were performed: anterior bicondylar angle, PCA, and condylar lengths with respect to the surgical transepicondylar axis. Ratios were calculated in relation to the femoral width. TD was classified according to the Dejour classification in grade A or grades B-C-D. An analysis of variance and a linear model were performed within some groups to investigate which parameters correlated with the classification's grade. RESULTS: This study showed a link between TD and the PCA: control group (1.4?±?0.2°), type A group (1.6?±?0.3°), and types B, C, D group (2.6?±?0.3°) (p?=?0.01). The difference between the control group and types B, C, D TD group was significant (p?=?0.002). In groups B, C, D, the PCA was more important, which proves that in these groups the posterior part of the lateral condyle was relatively shorter compared to the medial condyle. The greater the dysplasia, the longer the medial condyle was in the anterior posterior (p?=?0.02). CONCLUSIONS: This study shows not only an anterior but also a posterior anomaly in PI with TD. There is a correlation between the severity of the anterior deformation and the PCA: in other words, the knee is placed in valgus in flexure which promotes the external dislocation of the patella. This anatomical study could open a field of research on the development of surgical treatments based on the correction of posterior condylar femoral anomalies in PI. LEVEL OF EVIDENCE: III.

International audience; OBJECTIVE: The long-term impact of treatment strategies proposed by the IDSA guidelines for patients presenting with methicillin-susceptible S. aureus (MSSA) prosthetic joint infection (PJI) is not well-known. PATIENTS AND METHODS: Retrospective (2000-2010) cohort study including patients presenting with MSSA hip or knee PJI. A univariate Cox analysis was performed to determine if the non-compliance with IDSA surgical guidelines was a risk factor for treatment failure. RESULTS: Eighty-nine patients with a mean follow-up of 2.8 years were included. Non-compliance with IDSA surgical guidelines was associated with treatment failure (hazard ratio 2.157; 95% CI [1.022-4.7]). The American Society of Anesthesiologists score, inadequate antimicrobial therapy, and a rifampicin-based regimen did not significantly influence patient outcome. CONCLUSION: Based on the IDSA guidelines, if a patient presenting with MSSA PJI is not eligible for implant retention, complete implant removal is needed to limit treatment failure.

Previous research has demonstrated that women have a higher risk of anterior cruciate ligament (ACL) injury than men. Tibiofemoral articular geometry may play a role in the occurrence of ACL tears. The purpose of this study was to analyze the gender-specific geometric characteristics differences in tibiofemoral morphology in ACL-deficient patients. Medial tibial slope (MTS), lateral tibial slope (LTS), medial tibial plateau concavity, medial and lateral femoral condyle convexity, and lateral plateau convexity were analyzed in 276 patients with complete ACL injuries (138 females and 138 males). Two blinded observers measured the anatomical parameters of tibiofemoral geometry with use of multiplanar CT scans. Intra- and inter-rater reliabilities were assessed and comparisons between anatomic measures were made between male and female patients. The average ICC for all measurements was 0.90 (range 0.83–0.97) indicating good reliability. Male ACL injured patients demonstrated significantly greater LTS (10.5° ± 2.8) than female patients (9.6° ± 3.5°; p

Total knee arthroplasty (TKA) is frequently performed for obese patients. TKA in this population shows a high rate of complication, particularly tibial component loosening. The aim of this study is to compare the survival rate of tibial components in obese population using TKA with stem versus without stem. From a prospective database of 4216 TKA, obese patients [body mass index (BMI) > 30 kg m²] with primary TKA using a tibial short stem extension (30 mm) at a minimum follow-up of 2 years were retrospectively reviewed and compared to a matched control group (1:3 ratio) with a standard tibial stem. Inclusion criteria were BMI > 30 kg m², first knee surgery and 24 months minimum of follow-up. The primary outcome was revision for tibial aseptic loosening. Secondary outcomes were all-cause revisions and Knee Society Scores (KSS). The final study population consisted of 35 TKA with tibial extension stem versus 105 TKA with standard stem. The mean age was 69.2 and 69.5 years, respectively, with a mean follow-up of 52 months. Both groups were comparable before surgery. After 2 years of follow-up, we observed seven tibial loosening in the group without stem (6.6%) versus no tibial loosening in the stemmed group (p

Background To assess anatomic risk factors for meniscal lesions in association with acute ACL rupture. The primary hypothesis was that tibiofemoral anatomic measures will be different in those with and without concomitant meniscus tears. Methods A retrospective review of patients who underwent acute ACL reconstruction in the department was performed. All patients underwent a postoperative CT scan. The concavity and/or convexity on the femur and the tibia were measured by two blinded observers on the sagittal plane with different ratios, and these measures were compared in patients with and without meniscus tears in each compartment. Intra- and inter-rater reliabilities were assessed. Results Four hundred twelve patients (268 males and 144 females) were included from October 2012 to February 2015. One hundred sixty-seven patients had a medial meniscal tear (119 males/48 females), and 100 had a lateral meniscal tear (80 males/20 females). The mean time from injury to surgery was 3 months. The average ICC for all measurements was 0.87 (range 0.82–0.98) indicating good reliability. The medial femoral condyle was noted to be significantly longer than the medial tibial plateau in the sagittal plane in patients with a medial meniscal tear (p = 0.04), and the lateral femoral condyle was noted to be significantly longer than the lateral tibial plateau in the sagittal plane in patients with a lateral meniscal tear (p

The purpose of this study was to report the long-term outcomes of a continuous series of patients who underwent simultaneous anterior cruciate ligament (ACL) reconstruction and opening wedge high tibial osteotomy (HTO) for varus-related early medial tibio-femoral osteoarthritis. It was hypothesized that this combined surgery sustainably allowed return to sport with efficient clinical and radiological results. From 1995 to 2015, all combined ACL reconstruction (bone-patellar tendon-bone graft) and opening wedge HTO for anterior laxity and early medial arthritis were included. Clinical evaluation at final follow-up used Tegner activity score, Lysholm score, subjective and objective IKDC scores. Radiologic evaluation consisted in full-length, standing, hip-to-ankle X-rays, monopodal weight-bearing X-rays and skyline views. AP laxity assessment used Telos™ at 150 N load. Student’s t test was performed for matched parametric data, Wilcoxon for nonparametric variables and Friedman test was used to compare small cohorts, with p

The use of rotating-hinge total knee arthroplasties (TKA), despite several developments in prosthetic design, remains controversial. Results as well as indications of these devices are still discussed in primary intention and for young patients. The aim was to analyze early complications and survival rate of rotating-hinge TKA in primary intention and for revisions. A retrospective study included all the patients operated for primary or revision TKA procedure using a rotating-hinge TKA between 2015 and 2018. Clinical and radiological data were collected before surgery and then at a minimum follow-up of 1 year. The primary endpoint was the aseptic revision-free survival rate. Secondary endpoints were the overall survival rate, IKS scores, range of motion and patellar complications. Forty patients were included at an average follow-up of 18 months. Primary implantation was performed for 12 patients (30%), and revision for 28 cases (70%). At a mean follow-up of 18 months, only one implant was removed for a septic cause. The cumulative survival rate at 24 months was 95%. At final review, eight knees (20%) had been revised, five (12.5%) due to infection, two (5%) because of extensor mechanism failure, two (5%) for global stiffness. The objective and subjective IKS were significantly higher postoperatively in both primary and revision groups (p

PURPOSE: Total knee arthroplasty (TKA) is the treatment of choice for severe osteoarthritis of the knee. Many studies have been performed comparing mobile- and fixed-bearing designs; however, there are insufficient data regarding the patellar position in either system. This study aimed to compare the resultant patellar position with a mobile- versus a fixed-bearing TKA and the influence of both designs on clinical outcomes. MATERIALS AND METHODS: In this prospective randomized study, between 2007 and 2009, 160 TKA patients were assessed; 79 received a mobile-bearing and 81 received a fixed-bearing implant, for medial compartment osteoarthritis. A posteriorly stabilized, HLS Noetos knee prosthesis (Tornier, Saint-Ismier, France) was used in all cases. The only difference between the groups was whether the tibial component incorporated a fixed or mobile bearing. The patella was resurfaced in all cases. The International Knee Society Score (KSS) and the patellar tilt and translation were compared post-operatively. Patellar translation and patellar tilt analyses were subdivided into two subgroups (?5mm and??5°). RESULTS: The KSS was not statistically different between the groups at a mean follow-up of 7.4years (range 5-11years). Patellar translation and patellar tilt were not statistically different between the groups. When considering the patellar translation subgroup analysis, a significantly increased risk of patellar translation, greater than 5mm, was found in the mobile-bearing group compared to fixed-bearing group (OR?=?2.3; p?=?0.048) without generating any meaningful difference in clinical outcomes. CONCLUSION: The theoretical advantages of mobile-bearing implants compared to fixed-bearing implants were not demonstrated in this randomized study, at mid-term follow-up. In daily practice, the choice between mobile-bearing and fixed-bearing designs should be based on the experience and clinical judgment of the surgeon. LEVEL OF EVIDENCE: Prospective randomized study, level I.

Background Optimal treatment of prosthetic joint infection and chronic osteomyelitis consists of surgical removal of biofilm-embedded bacteria, followed by a 6–12 week course of antimicrobial therapy. However, when optimal surgery is not feasible, oral prolonged suppressive antibiotic therapy (PSAT) is recommended to prevent prosthesis loosening and/or relapse of infection. Since 2010, we have used infection salvage therapy using off-label subcutaneous (sc) injection of a β-lactam as PSAT for patients in whom oral PSAT is not possible. Methods A single-centre prospective cohort study (2010–18) reporting treatment modalities, efficacy and safety in all patients receiving sc PSAT. NCT03403608. Results The 10 included patients (median age 79 years) had polymicrobial (n = 5) or MDR bacterial (n = 4) prosthetic joint infection (knee, n = 4; hip, n = 3) or chronic osteomyelitis (n = 3). After initial intensive therapy, seven patients received ertapenem, three patients received ceftriaxone and one patient received ceftazidime by sc injection (one patient received 8 days of ceftriaxone before receiving ertapenem). In one patient, sc PSAT failed with recurrent signs of infection under treatment. In three patients, sc PSAT had to be discontinued due to side effects; in only one of these was the sc route implicated (skin necrosis following direct sc injection and not gravity infusion). Median treatment duration was 433 days. In six patients, sc PSAT was successful with favourable outcome at the time of writing. Interestingly, three patients with MDR bacterial carriage at baseline lost this under PSAT during follow-up. Conclusions As salvage therapy, sc PSAT delivered by gravity infusion is a safe and interesting alternative when an optimal surgical strategy is not feasible and no oral treatment is available.

International audience; Background Daptomycin has been recognized as a therapeutic option for the treatment of bone and joint infection (BJI). Gene polymorphism of ABCB1, the gene encoding P-glycoprotein (P-gp), may influence daptomycin pharmacokinetics (PK). Objectives We aimed to examine population PK of daptomycin and its determinants, including genetic factors, in patients with BJI. Patients and methods We analysed data from patients who received daptomycin for BJI between 2012 and 2016 in our regional reference centre and who had measured daptomycin concentrations and P-gp genotyping. A population approach was used to analyse PK data. In covariate analysis, we examined the influence of three single nucleotide variations (SNVs) of ABCB1 (3435C\textgreaterT, 2677G\textgreaterT/A and 1236C\textgreaterT) and that of the corresponding haplotype on daptomycin PK parameters. Simulations performed with the final model examined the influence of covariates on the probability to achieve pharmacodynamic (PD) targets. Results Data from 81 patients were analysed. Daptomycin body CL (CLDAP) correlated with CLCR and was 23% greater in males than in females. Daptomycin central V (V1) was allometrically scaled to body weight and was 25% lower in patients with homozygous CGC ABCB1 haplotype than in patients with any other genotype. Simulations performed with the model showed that sex and P-gp haplotype may influence the PTA for high MIC values and that a dosage of 10mg/kg/24h would optimize efficacy. Conclusions Daptomycin dosages higher than currently recommended should be evaluated in patients with BJI. Gender and P-gp gene polymorphism should be further examined as determinants of dosage requirements.

Purpose: Soft tissue balancing is of central importance to outcome following total knee arthroplasty (TKA). However, there are lack of data analysing the effect of tibial bone cut thickness on valgus laxity. A cadaveric study was undertaken to assess the biomechanical consequences of tibial resection depth on through range knee joint valgus stability. We aimed to establish a maximum tibial resection depth, beyond which medial collateral ligament balancing becomes challenging, and a constrained implant should be considered.Methods: Eleven cadaveric specimens were included for analysis. The biomechanical effects of increasing tibial resection were studied, with bone cuts made at 6, 10, 14, 18 and 24 mm from the lateral tibial articular surface. A computer navigation system was used to perform the tibial resection and to measure the valgus laxity resulting from a torque of 10 Nm. Measurements were taken in four knee positions: 0° or extension, 30°, 60° and 90° of flexion. Intra-observer reliability was assessed. A minimum sample size of eight cadavers was necessary. Statistical analysis was performed using a nonparametric Spearman's ranking correlation matrix at the different stages: in extension, at 30°, 60° and 90° of knee flexion. Significance was set at p?Results: There was no macroscopic injury to the dMCL or sMCL in any of the specimens during tibial resection. There was no significant correlation found between the degree of valgus laxity and the thickness of the tibial cut with the knee in extension. There was a statistically significant correlation between valgus laxity and the thickness of the tibial cut in all other knee flexion positions: 30° (p

PURPOSE: The aim of this case-control study was to compare implant position and revision rate for UKA, performed with either a robotic-assisted system or with conventional technique. METHODS: Eighty UKA (57 medial, 23 lateral) were performed with robotic assistance (BlueBelt Navio system) between 2013 and 2017. These patients were matched with 80 patients undergoing UKA using the same prosthesis, implanted using conventional technique. The sagittal and coronal component position was assessed on postoperative radiographs. The revision rate was reported at last follow-up. RESULTS: The mean follow-up was 19.7 months ±?9 for the robotic-assisted group, and 24.2 months ±?16 for the control group. The rate of postoperative limb alignment outliers (±?2°) was significantly higher in the control group than in the robotic-assisted group for both lateral UKA (26% in robotic group versus 61% in control group; p?=?0.018) and medial UKA (16% versus 32%, resp.; p?=?0.038). The coronal and sagittal tibial baseplate position had significantly less outliers (±?3°) in the robotic-assisted group, than in the control group. Revision rates were: 5% (n?=?4/80) for robotic assisted UKA and 9% (n?=?7/80) for conventional UKA (n.s.). The reasons for revision were different between groups, with 86% of revisions in the control group occurring in association with component malposition or limb malalignment, compared with none in the robotic-assisted group. CONCLUSION: Robotic-assisted UKA has a lower rate of postoperative limb alignment outliers, as well as a lower revision rate, compared to conventional technique. The accuracy of implant positioning is improved by this robotic-assisted system. LEVEL OF EVIDENCE: Level of evidence III. Retrospective case-control study CLINICAL RELEVANCE: This is the first paper comparing implant position, clinical outcome, and revision rate for UKA performed using the Navio robotic system with a control group.

Introduction: The number of total knee replacements performed (TKR) is increasing and so are patient expectations and functional demands. The mean age at which orthopedic surgeons may indicate TKR is decreasing, and therefore return to sport (RTS) after TKR is often an important expectation for patients. The aim of this study was to analyze the mid-term RTS, recreational activities, satisfaction level, and forgotten joint level after TKR. Methods: Between January 2015 and December 2016, 536 TKR (same implant design, same technique) were performed in our center. The mean age at survey was 69 years with a mean follow-up of 43 months. All patients who did not have a follow-up in the last 6 months were called. Finally, 443 TKR were analyzed. RTS was assessed using the University of California Los Angeles Scale (UCLA), forgotten joint score (FJS), and Satisfaction Score. Results: In this study, 85% of patients had RTS after TKR with a mean UCLA score increasing from 4.48 to 5.92 and a high satisfaction rate. Satisfaction with activity level was 93% (satisfied and very satisfied patients). The RTS is more important for people with a higher preoperative UCLA score and a lower American Society of Anesthesiologist score (ASA). Each point increase in ASA score is associated with reduced probability to RTS by 52%. Discussion: RTS and recreational activity were likely after TKR with a high satisfaction score. Preoperative condition and activity are the two most significant predictive factors for RTS. Level of evidence: Retrospective case series, level IV.

Introduction: PJI is the most dramatic complication after joint arthroplasty. In patients with chronic infection, prosthesis exchange is in theory the rule. However, this surgical approach is sometimes not desirable especially in elderly patients with multiple comorbidities, as it could be associated with a dramatic loss of function, reduction of the bone stock, fracture, or peroperative death. We propose here to report different approaches that can help to maintain the function in such patients based on a pathophysiology-, multidisciplinary-, and an experience-based approach. Methods: We describe the different points that are needed to treat such patients: (i) the multidisciplinary care management; (ii) understanding the mechanism of bacterial persistence; (iii) optimization of the conservative surgical approach; (iv) use of suppressive antimicrobial therapy (SAT); (v) implementation of innovative agents that could be used locally to target the biofilm. Results: In France, a nation-wide network called CRIOAc has been created and funded by the French Health ministry to manage complex bone and joint infection. Based on the understanding of the complex pathophysiology of PJI, it seems to be feasible to propose conservative surgical treatment such as “debridement antibiotics and implant retention” (with or without soft-tissue coverage) followed by SAT to control the disease progression. Finally, there is a rational for the use of particular agents that have the ability to target the bacteria embedded in biofilm such as bacteriophages and phage lysins. Discussion: This multistep approach is probably a key determinant to propose innovative management in patients with complex PJI, to improve the outcome. Conclusion: Conservative treatment has a high potential in patients with chronic PJI for whom explantation is not desirable. The next step will be to evaluate such practices in nation-wide clinical trials.