One-stage exchange strategy with extensive debridement for chronic periprosthetic joint infection following total knee arthroplasty is associated with a low relapse rate in non-selected patients: a prospective single-center analysis.

PURPOSE: This prospective clinical cohort was undertaken to determine the long-term risks of reinfection and all-cause aseptic failure after 1-stage exchange total knee arthroplasties (TKA) in a large series of consecutive patients with periprosthetic joint infection (PJI) following TKA. HYPOTHESIS: One-stage exchange for chronic PJI is an effective strategy, even in a non-selected population. PATIENTS AND METHODS: Non-selected patients (152 with 154 PJI) undergoing 1-stage-exchange TKA for PJI (January 2003-August 2015) were prospectively included and monitored for ≥2 years. PJI following TKA satisfying Musculoskeletal Infection Society diagnostic criteria were documented by microbiological culture results of preoperative joint aspirates and/or intraoperative samples. The cumulative incidences of total reinfections (i.e., relapses or new infections) and aseptic revisions were assessed. The mean follow-up (FU) duration was 7.5 years post-reimplantation. RESULTS: At the last follow-up, 35 knees had developed reinfections: 7 relapses and 28 new infections, with respective 14-year cumulative incidences of 4.8% and 20.6%. The 2-, 5- and 14-year cumulative total reinfection incidences were 12.3%, 21.3% and 24.3%, respectively. Respective 2-, 5-, 10- and 14-year aseptic component-revision incidences were 0.7%, 3.2%, 5.4% and 13.4%. Multivariate analysis retained male sex (HR 3.27, p < 0.01) and preoperative atrial fibrillation (HR 3.03; p = 0.01) as being significantly associated with greater risk of reinfection. CONCLUSIONS: One-stage-exchange TKA with aggressive debridement for chronic PJI is apparently a valid strategy, even for non-selected patients. It was associated with a low relapse rate, prevented morbidity and avoided economic social costs of 2-stage exchange. New infections with a different microorganism were observed more frequently and occurred even after years of FU. LEVEL OF EVIDENCE: II; Therapeutic.

Managing early complications in total hip arthroplasty: the safety of immediate revision.

PURPOSE: Immediate revision refers to a reoperation that involves resetting, draping, and exchanging the implant, after wound closure in total hip arthroplasty. The purpose of this study is to investigate the impact of immediate revision after total hip arthroplasty on subsequent infection and complication rates. METHODS: A total of 14,076 primary total hip arthroplasties performed between 2010 and 2020 were identified in our institutional database, of which 42 underwent immediate revision. Infection rates were determined 2 years after the index arthroplasty. The cause and type of revision, duration of primary and revision surgeries, National Nosocomial Infections Surveillance score, implant type, changes in implants, complications, and preoperative and intraoperative antibiotic prophylaxis were all determined. RESULTS: No infections were observed within 2 years after the index arthroplasty. Leg length discrepancy (88%, n = 37) and dislocation (7.1%, n = 3) were the main causes of immediate revision. In most cases of discrepancy, the limb was clinically and radiologically longer before the immediate revision. The mean operative time was 48 ± 14 min for the primary procedure and 23.6 ± 9 min for the revision. The time between the first incision and last skin closure ranged from 1 to 3 h. None of the patients were extubated between the two procedures. Two patients had a National Nosocomial Infections Surveillance score of 2, 13 had a score of 1, and 27 had a score of 0. CONCLUSION: Immediate revision is safe for correcting clinical and radiological abnormalities, and may not be associated with increased complication or infection rates. STUDY DESIGN: Retrospective cohort study; level of evidence, 3.

Are self-reported anthropometric data reliable enough to meet antibiotic prophylaxis guidelines in orthopedic surgery?

BACKGROUND: Surgical site infection is a serious complication in orthopedic surgery. The use of antibiotic prophylaxis (AP) combined with other prevention strategies has been shown to reduce this risk to 1% for hip arthroplasty and 2% for knee arthroplasty. The French Society of Anesthesia and Intensive Care Medicine (SFAR) recommends doubling the dose when the patient's weight is greater than or equal to 100 kg, and the body mass index (BMI) is greater than or equal to 35 kg/m2. Similarly, patients with a BMIgreater than40 kg/m2 orlesser than18 kg/m2 are ineligible for surgery in our hospital. Self-reported anthropometric measurements are commonly used in clinical practice to calculate BMI, but their validity has not been assessed in the orthopedic literature. Therefore, we conducted a study comparing self-reported with systematically measured values and observed the impact these differences may have on perioperative AP regimens and contra-indications to surgery. HYPOTHESIS: The hypothesis of our study was that self-reported anthropometric values differed from those measured during preoperative orthopedic consultations. MATERIALS AND METHODS: This single-center retrospective study with prospective data collection was conducted between October and November 2018. The patient-reported anthropometric data were first collected and then directly measured by an orthopedic nurse. Weight was measured with a precision of 500 g and height was measured with a precision of 1 cm. RESULTS: A total of 370 patients (259 women and 111 men) with a median age of 67 years (17-90) were enrolled. The data analysis found significant differences between the self-reported and measured height [166 cm (147-191) vs. 164 cm (141-191) (p<0.0001)], weight [72.9 kg (38-149) vs. 73.1 kg (36-140) (p<0.0005)] and BMI [26.3 (16.2-46.4) vs. 27 (16-48.2) (p<0.0001)]. Of these patients, 119 (32%) reported an accurate height, 137 (37%) an accurate weight, and 54 (15%) an accurate BMI. None of the patients had two accurate measurements. The maximum underestimation was 18 kg for weight, 9 cm for height, and 6.15 kg/m2 for BMI. The maximum overestimation was 28 kg for weight, 10 cm for height, and 7.2 kg/m2 for BMI. The verification of the anthropometric measurements identified another 17 patients who had contra-indications to surgery (12 with a BMI>40 kg/m2 and 5 with a BMI<18 kg/m2) and who would not have been detected based on the self-reported values. CONCLUSIONS: Although patients underestimated their weight and overestimated their height in our study, these had no impact on the perioperative AP regimens. However, this misreporting failed to detect potential contraindications to surgery. LEVEL OF EVIDENCE: IV; retrospective study with prospective data collection and no control group.

Revision total hip arthroplasty by a ceramic bearing surface after a third- and fourth-generation ceramic head or liner fracture.

PURPOSE: Although rare, fractures of ceramic components are difficult to revise, mainly due to the presence of residual ceramic debris that can cause catastrophic wear of the replacement components. Modern ceramic-on-ceramic bearings are suggested to improve outcomes of revision total hip arthroplasty (THA) for ceramic fractures. However, there are few published reports of mid-term outcomes of revision THA using ceramic-on-ceramic bearings. We evaluated clinical and radiographic outcomes of 10 patients who received ceramic-on-ceramic bearings during revision THA for ceramic fractures. METHODS: All patients but one received fourth-generation Biolox Delta bearings. Clinical evaluation was performed using the Harris hip score at latest follow-up, and all patients received a radiographic evaluation to analyze the fixation of the acetabular cup and of the femoral stem. Osteolytic lesions and the presence of ceramic debris were noted. RESULTS: After a mean follow-up of 8.0 years, there were no complications or implant failures, and all patients reported satisfaction with their implant. The average Harris hip score was 90.6. There was neither osteolysis nor loosening, but despite our extensive synovial debridement, ceramic debris was noted in the radiographs of five patients (50%). CONCLUSION: We report excellent mid-term outcomes, with no implant failures after eight years despite ceramic debris being found in a significant proportion of patients. We conclude that modern ceramic-on-ceramic bearings are an advantageous option for the revision of THA due to the fracture of initial ceramic components.

Systematic alignments yield balanced knees without additional releases in only 11% of knee arthroplasties: a prospective study.

PURPOSE: The literature suggests that "forgotten" knees are the most stable knees postoperatively. The main objective of our study was to determine whether a systematic alignment (mechanical, anatomical or kinematic) makes it possible to stabilise the operated joint in extension and in flexion. METHODS: This monocentric prospective cohort study was conducted between May 1st, 2021 and October 31st, 2021. A total of 132 consecutive patients undergoing primary navigated total knee arthroplasty were included, with a mean age of 72.4 years (7.9; 48.8-91.2 years), a mean body mass index (BMI) of 28.6 kg/m2 (4.6; 17.6-41.6) and 71.2% (94/132) women. Mechanical, anatomical and kinematic knee alignments were simulated using Kick software for each patient. The primary outcome was the targeted rate of balanced knees for each type of alignment, based on a three-point score, aiming for a 3/3 score for each knee. Our secondary outcome was to characterise the specific implantation finally achieved by the surgeon. RESULTS: The targeted balance was reached in 10.6% (14/132), 10.6% (14/132) and 12.9% (17/132) of knees with mechanical, anatomical and kinematic alignment simulations, respectively. None of these simulations provided a superior number of balanced knees (p = 0.87). When simulating a patient-specific implantation, the highest score was reached in 89.1% (115/132) of cases. CONCLUSION: Systematic alignment simulations achieved knee balance in only 11% of cases. Patient-specific implantation, favouring knee balancing over alignment, allowed an 89% perfect score rate without having to perform any collateral release. LEVEL OF EVIDENCE: Case series. Level 4.

Doctor, what does my ceramic-on-ceramic hip arthroplasty weigh?

BACKGROUND: While total hip arthroplasty (THA) is generally very successful, certain patients remain dissatisfied. A common concern, especially in younger and more active patients, is the weight the implant will add to the hip. However, there is very little data available to help guide surgeons in addressing this concern. The goal of this study was therefore to compare the weight of the total hip arthroplasty implants to that of tissue removed. HYPOTHESIS: That the weight of the total hip arthroplasty implants would exceed that removed tissue. PATIENTS AND METHODS: A prospective study was conducted in 104 patients, without interfering with surgical plans. To account for different implant designs, especially relating to stem fixation, we included both cementless (n=51) and cemented (n=53) femoral stems. During the procedure, the removed bone and soft tissues, as well as the post-implantation cement were collected and weighed. The weight of the implants was provided by the manufacturer. RESULTS: Both cemented and cementless THA implants proved significantly heavier than the removed bone and soft tissues. The median weight gained was 145g [IQR: 123-168] with the cementless implant and 241g [221-364] with the cemented implant (p<0.001). Multivariable regression analysis of patient- or implant factors influencing weight gain after THA revealed that weight gain decreased with patient BMI (ß=-1.0, 95% CI: -2.0--0.1 (p=0.034)). In contrast, weight gain increased slightly with total implant weight (ß=0.7, 95% CI: 0.6-0.8 (p≤0.001)). Further, weight gain was greater for women (ß=19.0, 95% CI: 9.1-29.0 (p≤0.001) (men 150g [135-219], women 211g [157-250] (p=0.010)) and patients who received the cemented stem (ß=40.0, 95% CI, 19.4-46.5, p≤0.001). DISCUSSION: Current models cause a two- to three-fold gain of weight at the hip joint after THA. While it is not clear whether this weight increase has any clinical repercussions, this finding can be helpful when a patient raises questions on this topic during the preoperative counseling. More research is necessary to determine whether lighter implants may be beneficial for patients. LEVEL OF EVIDENCE: III, case control study.

One-Stage Exchange Arthroplasty for Fistulizing Periprosthetic Joint Infection of the Hip: An Effective Strategy.

Background: Prosthetic hip infection (PHI) is a disastrous scenario after an arthroplasty. International guidelines contraindicate one-stage exchange arthroplasty for fistulizing chronic prosthetic hip infection (FCPHI), nevertheless few surgical teams, mostly from Europe, support one stage procedure for this indication. Questions/Purposes: Analysis of infection recurrence and implant failure of a series of FCPHIs treated with one stage arthroplasty. Patients and Methods: Sixty-six FCPHIs treated with one-stage exchange arthroplasty were prospectively followed up at least 2 years. Clinical, radiological and bacteriological signs suggestive of reinfection were sought, as well as implant failures and PHI related deaths. Results: Thirty-four females and thirty-two males with median age of 69.5 years [61-77] and BMI of 26 kg/m2 [22-31] were included. Fistulae were productive in 50 patients (76%). Staphylococcus was responsible for 45% of PHI and 21% were polymicrobial. Twenty-nine patients (44%) received preoperative antibiotic therapy. After a median 60-month follow-up [35-82], 3 patients (4.5%) presented reinfection (two new infections, one relapse) and 3 patients experienced implant failure (1 femoral fracture, 1 stem breakage, 1 recurrent dislocation). One death was related to PHI. After a minimum of 2 years, the infection control rate was of 95.3% (±0.02). Conclusion: One-stage exchange arthroplasty for FCPHIs showed a good infection control rate similar to that of non-fistulizing PHI. Systematic preoperative microbiological documentation with joint aspiration and, in some specific cases, the use of preoperative antibiotic therapy are among the optimizations accounting for the success of the one-stage arthroplasty. In light of these results, and those of other studies, international recommendations could evolve. Level of Evidence: Descriptive therapeutic prospective cohort study. Level of evidence: IV.

Haematogenous prosthetic knee infections: Prospective cohort study of 58 patients.

BACKGROUND: Prosthetic joint infection (PJI) is a rare (incidence, 0.15% to 0.9%) but serious complication of knee arthroplasty. Haematogenous PJI of the knee (KhPJI) which accounts for 10% of cases, has been less studied than PJI due to other mechanisms. The primary objective of this study in patients with KhPJI of the knee was to determine the 2-year infection eradication failure rate after either exchange arthroplasty or arthrotomy/synovectomy/irrigation (ASI), combined with prolonged peri-operative antibiotic therapy, at a referral centre for complex osteo-articular infections. HYPOTHESIS: ASI within 2 weeks after symptom onset and one-stage exchange arthroplasty produce similar 2-year success rates in patients with KhPJI of the knee. MATERIAL AND METHODS: A prospective observational cohort study was performed in patients managed for PJI of the knee between 2003 and 2015. The primary outcome measure was the occurrence of a septic event or of KhPJI -related death during a minimum follow-up of 2 years. RESULTS: Of 265 patients with PJI after total knee arthroplasty, 58 (22.1%) had KhPJI with onset more than 3 months after the last arthroplasty procedure and were included in the study. Among them, one-third had immune deficiencies. The most common causative organisms were streptococci (n=25, 43%) and Staphylococcusaureus (n=20, 34%). The primary focus of infection was identified in only 64% of patients and was most often cutaneous (n=19, 33%) or dental (n=11, 19%). A septic event or KhPJI-related death occurred in 5/34 (15%) patients after one-stage exchange arthroplasty and 6/19 (32%) patients after ASI within 15 days after symptom onset (p=0.03). Patient characteristics, type of prosthesis, and causative organism were not significantly associated with failure to eradicate the infection. CONCLUSION: ASI carried a high failure rate despite being performed within 15 days after symptom onset. One-stage exchange arthroplasty seems to be the best surgical option, particularly as the exact time of symptom onset may be difficult to determine. Identifying and eradicating the primary focus of infection is crucial. LEVEL OF EVIDENCE: II, low-powered prospective cohort study.

Doctor, what does my knee arthroplasty weigh?

The aim of this study was to compare the weight of the total knee arthroplasty (TKA) implants and the weight of the natural knee. A prospective study was conducted with two different brands of cemented primary TKA. During the procedure, we collected the removed bone, soft tissues and the post-implantation cement and weighed them all separately at the end. In both groups, the implants plus cement were significantly heavier than the removed bone and soft tissues. The average weight gained was 266.7 ± 35.1 g for group 1 and 279.1 ± 48.7 g for group 2. This significant local weight gained after TKA is a new parameter that should be taken into account for further studies and when creating new implants.