Is Dual Antibiotic-Loaded Bone Cement More Effective and Cost-Efficient Than a Single Antibiotic-Loaded Bone Cement to Reduce the Risk of Prosthetic Joint Infection in Aseptic Revision Knee Arthroplasty?

BACKGROUND: Higher rates of prosthetic joint infections (PJIs) are related to patient risk factors and/or to special surgical procedures such as revision total knee arthroplasty (rTKA). Among the measures discussed to better protect those patients from the higher infection risks use of dual antibiotic-loaded bone cement has emerged as a further prophylactic option. METHODS: This retrospective study included 246 patients undergoing strictly aseptic revision knee arthroplasty at our institution in the time period 2015-2018. Based on the type of bone cement used for the cementation of the revision prosthesis, 2 groups were defined. In total, 143 patients received the low-dose single antibiotic-loaded bone cement (SALBC) PALACOS R+G and 103 patients received the high-dose dual antibiotic-loaded bone cement (DALBC) COPAL G+C. The number of PJI cases in each group over a follow-up time of minimum 1 year was compared and the extra costs for the DALBC use calculated against the economic savings per each avoided PJI case on basis of 3 different assumptions (treatment costs and amount of cement use). RESULTS: Use of DALBC in aseptic rTKA was associated with a significant reduction in PJI cases (relative risk = 57%, PJI rate in the SALBC group 4.1% vs 0% in the DALBC group, P = 0.035). The calculated total savings per patient was $1367. Depending on the economic assumptions the range of savings was between $1413 (less favorable calculation model) and $3661 (most favorable calculation model). CONCLUSION: The use of DALBC in rTKA has been found to be more effective in preventing PJI and proved cost-efficient in all our cost-calculation models.

Is the Commercial Antibiotic-Loaded Bone Cement Useful in Prophylaxis and Cost Saving After Knee and Hip Joint Arthroplasty? The Transatlantic Paradox.

BACKGROUND: The use of antibiotic-loaded bone cement (ALBC) has proven to be effective in preventing periprosthetic infection (PPI) after total hip (THA) and knee arthroplasty (TKA). However, the economic benefit of using ALBC routinely remains controversial. METHODS: A total of 2518 patients subjected to THA, partial hip arthroplasty, and TKA between 2009 and 2012 were identified in our prospectively collected registry. Two groups were defined: before (2009-2010) and after the introduction of ALBC (2011-2012). The risks of PPI associated with each type of surgery in each group were determined and compared. Patients subjected to THA without cemented implants were used as controls, and possible bias associated with changes in infection rate during the study period and other variables were controlled. The costs of the use of ALBC were calculated, along with the savings per case of PPI avoided. The minimum follow-up for discarding PPI was 2 years. RESULTS: Following the introduction of ALBC, a global decrease of 57% was observed in the risk of PPI (P = .001). By type of surgery, the decrease was 60.6% in the case of TKA (P = .019) and 72.6% in the case of cemented hip arthroplasty (partial and total; P = .009). No decrease in infection rate was noted in uncemented hip arthroplasty (P = .42). The total saving associated with the use of ALBC was €1,123,846 (€992 per patient): €440,412 after TKA (€801 per patient) and €686,644 after cemented hip arthroplasty (€2672 per patient). CONCLUSION: The use of ALBC has been found to be effective in preventing PPI after TKA and hip arthroplasty, with a favorable cost-efficiency profile using standardized cost and infection rates in our setting.

Revision TKA with a condylar constrained prosthesis using metaphyseal and surface cementation: a minimum 6-year follow-up analysis.

BACKGROUND: The increasing number of revision knee arthroplasty result in the more frequently use of a constraint implant but results from previous reports are difficult to interpret. The purpose of this study was to compare the long-term outcomes of superficial cemented versus metaphyseal cemented in revision total knee arthroplasty with a condylar constrained arthroplasty. METHODS: The study was a retrospective analysis of clinical and radiographic outcomes in a series of revision total knee arthroplasties performed with a constrained condylar knee prosthesis and press-fit modular stems. We hypothesized that the clinical and radiographic outcome of surface cementation would be inferior to that of metaphyseal cementation. Fifty-two consecutive revision cases were followed for a median of 8.2 years (range, 6 to 10 years). RESULTS: Substantial improvements in range of motion and Knee Society score were achieved in all patients, although these were not significant between groups. Significantly more radiolucent lines were visible on the tibial component with surface cementation than with metaphyseal cementation, although the clinical differences were not relevant. CONCLUSIONS: Radiologic outcome was better in revision total knee arthroplasty using metaphyseal cemented revision and components with press-fit cementless stems than in the surface cementation-based approach; however, the difference was not clinically relevant.

How to remove a well-fixed metaphyseal sleeve in revision knee arthroplasty: A step-by-step surgical procedure.

BACKGROUND: The rising incidence and complexity of revision knee arthroplasty has led to an increase in the use of metaphyseal reconstruction systems. One of the most widely used systems are metaphyseal sleeves as they have demonstrated excellent long-term survival. However, there is concern about the possible difficulty of extracting a sleeve if it were necessary, as no known procedures have yet been validated. METHODS: We examined the outcomes of removing 23 well-integrated metaphyseal sleeves using the same systematized technique. RESULTS: All sleeves were extracted without any intraoperative complications. Four subjects required an osteotomy to complete the extraction, while 62% of the sample were found to have an AORI IIB defect. All cases were successfully reconstructed with a new metaphyseal fixation, implanting a new sleeve in 38% of subjects compared with cones in the remaining 62%. CONCLUSIONS: The technique described here produced successful, reproducible outcomes for the removal of integrated metaphyseal sleeves with minimal bone loss and no intraoperative complications.

Long-term outcomes of one single-design varus valgus constrained versus one single-design rotating hinge in revision knee arthroplasty after over 10-year follow-up.

BACKGROUND: The appropriate degree of constraint in knee prosthetic revision is unknown, necessitating the use of the lowest possible constraint. This study aimed to compare the long-term clinical and survival results of revision with rotation hinge knee (RHK) VS constrained condylar constrained knee (CCK) implants. METHODS: Overall, 117 revision case were prospectively reviewed and dividing into two groups based on the degree of constraint used, using only one prosthetic model in each group (61 CCK vs 56 RHK). All implants were evaluated for a minimum of 10 years. Survival of both implants at the end of follow-up, free from revision for any cause, aseptic loosening, and septic cause was compared. RESULTS: Better results were seen with use of the RHK in joint ranges of (p = 0.023), KSCS (p = 0.015), KSFS (p = 0.043), and KOOS (p = 0.031). About 22.2% of the cases required repeat surgery (11.7% RHK vs 29.6% CCK, p = 0.023). Constrained condylar implants had a significantly lower survival rates than rotating hinge implants (p = 0.005), due to a higher aseptic loosening rate (p = 0.031). CONCLUSION: Using a specific RHK design with less rotational constraint has better clinical and survival outcomes than implants with greater rotational constraint, such as one specific CCK.

Improvement of surgical time and functional results after do-it-yourself 3D-printed model preoperative planning in acetabular defects Paprosky IIA-IIIB.

INTRODUCTION: The correct positioning of the implant in revision total hip arthroplasty (rTHA) is critical to obtaining substantial functional outcomes, and to avoiding complications. Current literature supports three-dimensional (3D)-printed models as potentially useful tools for preplanning, as well as the "do it yourself (DIY)" methodology to reduce both the time and costs of this procedure. However, no study has determined the efficacy of both methods combined in a cohort of patients with severe acetabular defects. In the lack of bibliography, we performed rTHA after preoperative planning by DIY-3D-printed models to evaluate its influence in: 1) the surgical time, 2) the functional scores, 3) the intra and postoperative complications, and 4) the reconstruction of the center of rotation (COR) of the hip. HYPOTHESIS: Preoperative planning through 3D-DIY printed models will both improve the accuracy of the implant positioning, and the surgical time, leading the latter to improved functional scores and reduced complications. MATERIALS & METHODS: A comparative study of 21 patients with Paprosky IIB to IIIB acetabular defects who underwent rTHA after 3D-printed model preoperative planning by the DIY method between 2016 and 2019 was conducted. A historical cohort of 24 patients served as the comparator. Surgical time, reconstruction of the COR, functional scores, and complications were analyzed. RESULTS: The mean follow-up was 32.4 (range, 12 to 60) months. All the patients showed significant improvement of the Harris hip score (HHS) after the operation (3D group: 26.58±10.73; control group 22.47±15.43 (p=0.00)). In the 3D-printed model preoperative planning group the mean operation time and the intraoperative complications were significantly lower (156.15±43.03min vs 187.5±54.38min (p=0.045); and 19% vs 62.5% (p=0.003), respectively), and the HHS and patient satisfaction score (PSS) were significantly greater (83.74±8.49 vs 75.59±11.46 (p=0.019); and 8.17±0.88 vs 7.36±1.17 (p=0.023), respectively). No differences were found in the postoperative complications, nor in the restoration of the COR as determined from the acetabular index, verticalization or horizontalization, although the acetabular index was closer to the intended one in the 3D-printed model planning group (46.67°±7.63 vs 49.22±8.1 (p=0.284)). CONCLUSION: Preoperative planning of severe acetabular defects through 3D-printed models shortens the surgical time, leading to a decrease in complications and thus to better functional outcomes and greater patient satisfaction. Moreover, the DIY philosophy could decrease both the time and costs of traditional 3D planning. LEVEL OF EVIDENCE: III, retrospective case matched study.

A new biarticular cement spacer technique for infected total hip and knee arthroplasty with massive bone loss.

INTRODUCTION: The management of massive femoral bone defects following prosthetic infection remains a surgical challenge, particularly when the entire femur is affected. METHODS: We present the first results of a new biarticular cement spacer with antibiotic technique using a cephalomedullary nail for the treatment of infected hip arthroplasty involving complete femoral bone loss. RESULTS: 5 patients with a minimum follow-up of 1 year were included. In all cases 2-stage replacement due to hip periprosthetic infection was carried out, with the need for a biarticular complete femoral spacer in view of the magnitude of the bone defect. The infection was resolved in all patients, with no complications (spacer fracture or dislocation) associated to spacer use, and the patients were all able to maintain the sitting position with active knee movements between the 2 surgical stages. Improvement with respect to preoperative functional status was observed in all cases, as evidenced by the Harris Hip Score (HHS) (from 24.2 to 73; p < 0.001) and 12-Item Short-Form Health Survey (SF-12) (from 16.8 to 33.2; p = 0.001), with a lessened need for walking aids. DISCUSSION: The described technique offers a possible solution to a number of complications observed with the use of spacers in massive defects, affording greater patient comfort and autonomy while waiting to receive total femoral replacement.

Patient-Specific Instrument Can Improve Functional and Radiographic Results during Learning Curve for Oxford Unicompartmental Knee Arthroplasty.

The true value of use of patient-specific instrumentation (PSI) systems by inexperienced surgeons during their learning curve to improve the clinical and radiographic outcome of unicompartmental knee arthroplasty (UKA) has not been previously studied. Fifty patients with a mean age of 64.3 years undergoing surgery for Oxford UKA were prospectively divided into two groups. Twenty-five patients were operated on by a surgeon with no prior experience in UKA using a PSI system and the other 25 patients by an experienced surgeon using a conventional procedure. Patients were scored using joint range of motion (ROM), the Knee Society Score (KSS), the Knee Injury and Osteoarthritis Outcome Score (KOOS), and the 12-item Short-Form (SF-12) before and 3 months and 2 years after surgery. Impact of use of PSI was measured by comparing clinical and radiographic outcome, complications, and implant survival. No evidence of poorer clinical outcome was seen in any subscale of KSS, KOOS, and SF-12 for inexperienced surgeons using PSI (p = 0.45, p = 0.32, and p = 0.61, respectively). No difference was found between the two procedures in precision of radiographic alignment of components (p = 0.53). No complication occurred in any group. PSI may improve precision of component alignment during the learning curve of surgeons, thus achieving functional results similar to those of more experienced surgeons using a conventional procedure.

Biarticular total femur spacer for massive femoral bone loss: the mobile solution for a big problem.

Bone cement spacers loaded with antibiotic are the gold standard in septic revision. However, the management of massive bone defects constitutes a surgical challenge, requiring the use of different nails, expensive long stems, or cement-coated tumor prostheses for preparing the spacer. In most cases, the knee joint must be sacrificed. We describe a novel technique for preparing a biarticular total femur spacer with the help of a trochanteric nail coated with antibiotic loaded cement, allowing mobility of the hip and knee joints and assisted partial loading until second step surgery. This technique is helpful to maintain the length of the leg, prevent soft tissue contracture, and help eradicate the infection preserving the patient comfort and autonomy while waiting to receive total femoral replacement.

Does a new implant design with more physiological kinematics provide better results after knee arthroplasty?

BACKGROUND: Improved knee kinematics is one of the major goals to obtain better satisfaction after total knee arthroplasty. This study examined whether a guided motion knee design improves functional outcome and satisfaction as compared to a conventional design. METHODS: In a retrospective manner, from January 2005 to December 2008, patients with two different kinematic TKA designs were enrolled. The 150 patients were divided into two groups: guided motion group (77) with kinematic design (Journey) and control group (73) with no kinematic design (LCS). All the patients had the same surgical technique and postoperative protocols. The functional and radiographic results were interpreted with the Hospital for Special Surgery (HSS) knee score and WOMAC score. RESULTS: After a mean follow-up of 84.2months, the guided motion group had higher mean postoperative range of motion (p=0.022), functional status in the WOMAC function subscale (p=0.002), but had higher residual pain in the WOMAC pain subscale (p=0.018 and p=0.013) and higher iliotibial band syndrome incidence (6.6% vs 0%; p=0.02). There were no significant differences in HSS score between the two groups. No differences were seen between groups in patient satisfaction in the WOMAC total score (p=0.46) and survival rate. CONCLUSION: The guided motion design can improve functional status according to WOMAC but not to HSS knee scores. Poorer pain scores and no higher patient satisfaction were observed with this kinematic design.