French Hip & Knee Society classification of short-stem hip prostheses: Inter- and intra-observer reproducibility.

INTRODUCTION: In total hip replacement (THR), a short stem theoretically provides more physiological force transfer to the proximal femur, conserves bone stock and facilitates minimally invasive surgery. On the other hand, such implants involve a learning curve and incur risk of malpositioning or fracture and of secondary mobilization. There are several types of short stem, and classification is needed. Classifications exist, but are based more on implant length than on anchorage zone, and most have not been tested for reproducibility. The French Hip & Knee Society (SFHG) developed a short-stem classification based on anchorage zone inside the femur. The objectives of the present study were: (1) to present the classification, (2) to apply it to the short-stem models available in France and those widely used worldwide, and (3) to assess reproducibility. HYPOTHESIS: The SFHG short-stem classification enables reproducible comparison. MATERIAL AND METHOD: A short-stem classification according to anchorage zone was drawn up by an expert group. The stems and the classification were presented to 12 surgeons performing THR, who classified the stems according to the classification; a retest was performed 2 months later. RESULTS: The classification is based on femoral stem anchorage site, in 5 types: type 1, cephalic; type 2, isolated cervical; type 3, Calcar femorale; type 4, metaphyseal; and type 5, conventional metaphyseal-diaphyseal, with shortened stems. Inter-observer reproducibility was 92.7% [95%CI: 91.7%-93.6%], with kappa 0.785 [95%CI: 0.755-0.814], and Lin test-rest concordance correlation coefficient 0.852 [95%CI: 0.836-0.869]. Intra-observer reproducibility was 94.0% [95%CI: 91.9%-96.1%], with kappa 0.820 [95%CI: 0.759-0.882], and Lin test-retest concordance correlation coefficient 0.820 [95%CI: 0.792-0.849]. DISCUSSION: This new classification enables femoral implants to be reproducibly compared according to anchorage zone. LEVEL OF EVIDENCE: IV; retrospective study without control group.

Bone cement implantation syndrome in hip arthroplasty: Frequency, severity and prevention.

INTRODUCTION: Cemented femoral implants incur a serious risk of potentially fatal accidents in case of bone cement implantation syndrome (BCIS). As French data are sparse regarding this issue, Orthorisq, the official accreditation body for orthopedic surgeons, conducted an inter-professional survey: 1) to assess the frequency of BCIS, 2) to analyze risk factors related to the patient and to professional practices, and 3) to set out guidelines to reduce frequency and/or severity. HYPOTHESIS: French data on BCIS are underestimated and need updating to ease communication between colleagues. MATERIAL AND METHOD: In 2019, Orthorisq ran a survey of its members' practices and a "mirror" survey of anesthesiologists. In the decade from 2009 to 2018, the 775 respondent orthopedic surgeons, both occasional and systematic "cementers", reported their experience with a declared annual rate of 80,112 arthroplasties, including 63,799 (79.6%) in scheduled surgery. Some of the survey questions concerned cementing technique. With the help of the French College of Anesthesia and Intensive Care Medicine, 305 anesthesiologists responded to the mirror survey. RESULTS: The 776 orthopedic surgeons reported 1896 cementing accidents with 387 deaths during the study decade. Accidents were 6-fold more frequent in traumatology than in scheduled orthopedic surgery (0.71% versus 0.12%) and, more importantly, were more serious: mortality was 10-fold higher (0.17% versus 0.017% [p<0.001]). Certain "tricks and tips" intended to improve cementing quality, such as a dedicated system and especially a plug, significantly increased the risk of BCIS (p<0.001). Over the same period, the 305 anesthesiologists had been involved in 490 cementing accidents; 88 (29%) had been faced by at least 1 death, most often in emergency settings (60/28). While 753 surgeons (96%) reported warning the anesthetists and 571 (74%) waited for agreement before cementing, only 109 (36%) and 124 (41%) anesthetists reported being systematically alerted to cementing and implant reduction, respectively. The rate of serious accidents was 0.19% and mortality was 0.05%, for a cumulative probability of 0.24% per year. Extrapolated to the data of the ATIH Technical Agency of Hospitalization Information and subtracting arthroplasties by "never-cementers", these figures indicate 311 accidents with 65 deaths in femoral BCIS for 2018. DISCUSSION: In scheduled surgery, BCIS was exceptional, but the rate in traumatology was much higher. Certain techniques intended to improve femoral cementing quality actually increased the risk of BCIS; in high-risk patients, especially in traumatology, non-cemented femoral implants or else a 1st-generation cementing technique should therefore be preferred. Prevention of BCIS and/or reduction of severity require identification of at-risk patients and good communication between surgeons and anesthesiologists, especially at the various steps of the checklist. LEVEL OF EVIDENCE: IV; case series.

Bleeding and thromboembolism risk of standard antithrombotic prophylaxis after hip or knee replacement within an enhanced recovery program.

INTRODUCTION: Prevention of venous thromboembolism (VTE) generally consists of low molecular weight heparin (LMWH) or direct oral anticoagulants (DOACs) after total hip arthroplasty (THA) or total knee arthroplasty (TKA). Enhanced recovery after surgery (ERAS) protocols may reduce the VTE risk after these procedures. The aim of this study was to compare the risk of VTE and the risk of bleeding complications in a non-selected population of primary THA and TKA cases done within an ERAS protocol. HYPOTHESIS: The risk of postoperative VTE after primary THA and TKA is lower than the risk of bleeding complications within an ERAS protocol. METHODS: This was a prospective observational study conducted on a national scale in France. All patients who underwent primary unilateral THA or TKA at one of 11 participating hospitals between October 2016 and October 2017 were enrolled and followed for 3 months. The occurrence of a VTE or major bleeding event was recorded. No patients were lost to follow-up at 3 months. RESULTS: Of the 1110 THA cases, there were 5 VTE (0.4%) and 19 bleeding events (1.7%). Of the 893 TKA cases, there were 9 VTE (1.0%) and 14 bleeding events (1.7%). There was no significant difference in the VTE incidence and bleeding event incidence after THA and TKA. The overall incidence of bleeding complications (1.7%) was significantly greater than the overall incidence of VTE complications (0.7%) (p=0.005). This was the case after THA (p=0.004) but not after TKA. DISCUSSION: The primary finding of this study is that bleeding complications are significantly more common than VTE complications after THA or TKA within an ERAS protocol. Based on these findings, the cost-benefit ratio of antithrombotic prophylaxis by LMWH or DOACs in this context should be reassessed. LEVEL OF EVIDENCE: IV; Prospective cohort study without control group.

Fast track protocol for primary total hip arthroplasty in non-trauma cases reduces the length of hospital stay: Prospective French multicenter study.

BACKGROUND: Fast-track (FT) procedures continue to evolve; however, their benefits are still controversial. This led us to conduct a prospective study of FT procedures for total hip arthroplasty (THA) on a national scale in France with historical control data. The aims were to (1) evaluate the effectiveness of FT procedures after THA on the length of hospital stay (LOS) in a multicenter analysis, (2) measure the immediate return to home, rehospitalization and reoperation rates. HYPOTHESIS: FT procedures reduce the LOS after primary THA for non-traumatic indications relative to national historical data. METHODS: A prospective observational study was done at 11 hospital facilities throughout France. Patients who underwent primary THA for a non-traumatic condition and FT procedures were followed for 3 months. The average LOS, discharge to home, unexpected readmissions, and reoperation rate were compared to 2016 figures from the French national database of 104,745 procedures on the same population. RESULTS: The study included 1,110 patients, 499 men (45%) and 611 women (55%), with a mean age of 67.5±11.9 years. The average LOS was 3.3±2.9 days versus 7.5±5.3 days in the national database (p<0.001). Eight hundred eighty patients (79%) were discharged directly to home versus 72,577 (69%) in the national database (p<0.001). Forty-two patients (4%) were readmitted to the hospital within 90 days of the THA versus 11,092 (11%) in the national database (p<0.001). Eighteen patients (1.6%) were reoperated within 90 days of the THA procedure versus 2100 (2.0%) in the national database (p=0.72). DISCUSSION: FT procedures help to significantly reduce the average LOS and rehospitalization rate after primary THA for non-traumatic conditions and significantly increased the percentage of patients being discharged directly to home relative to national historical data, without altering the risk of reoperation. FT procedures should become the standard of care after THA. LEVEL OF EVIDENCE: III; prospective case-control study.

Early experience with dual mobility acetabular systems featuring highly cross-linked polyethylene liners for primary hip arthroplasty in patients under fifty five years of age: an international multi-centre preliminary study.

PURPOSE: To evaluate early performance of contemporary dual mobility acetabular systems with second generation annealed highly cross-linked polyethylene for primary hip arthroplasty of patients under 55 years of age. METHODS: A prospective observational five years study across five centers in Europe and the USA of 321 patients with a mean age of 48.1 years was performed. Patients were assessed for causes of revision, hip instability, intra-prosthetic dissociation, Harris hip score and radiological signs of osteolysis. RESULTS: There were no dislocations and no intra-prosthetic dissociations. Kaplan Meier analysis demonstrated 97.51% survivorship for all cause revision and 99.68% survivorship for acetabular component revision at five years. Mean Harris hip score was 93.6. Two acetabular shells were revised for neck-rim implant impingement without dislocation and ten femoral stems were revised for causes unrelated to dual mobility implants. CONCLUSION: Contemporary highly cross-linked polyethylene dual mobility systems demonstrate excellent early clinical, radiological, and survivorship results in a cohort of patients that demand high performance from their implants. It is envisaged that DM and second generation annealed HXLPE may reduce THA instability and wear, the two most common causes of THA revision in hip arthroplasty.

Are modern dual mobility cups a valuable option in reducing instability after primary hip arthroplasty, even in younger patients?

Hip instability after total hip replacement has been shown to be a critical cause of failure. The use of dual mobility has been classically restricted to patients "at risk", over 70 years of age. The question rises up about extended indications of so-called "modern" second generation dual mobility cups. This prospective multicenter study reports on first results at 2-5 years of the HA anatomical ADM cup upon two comparative groups of patients under 70 years (112 hips) vs. over 70 years of age (325 hips). No dislocation, migration, tilting, wear, or intra-prosthetic dislocation was recorded within each of the two cohorts. Survivorship for cup failures at this 4-year period was ideal at 100% in the younger patients, and 99.7% in the older group of patients.