Fused hip conversion to total hip arthroplasty with the direct anterior approach: surgical technique on a regular surgical table under fluoroscopic guidance.

PURPOSE: Conversion of a fused hip to a total hip arthroplasty (THA) is technically challenging due to the loss of anatomical references. Here, a reproducible technique using the direct anterior approach (DAA) with a regular surgical table under fluoroscopic guidance is described, which has several advantages over traditional such as lateral or posterior approaches. METHODS: There were reported 11 cases of ankylosis hip that were converted to THA using the same surgical technique protocol. Clinical and radiographic outcomes were recorded at 3.2 years of follow-up. A detailed preoperative evaluation was performed, including a pelvis radiological evaluation and magnetic resonance image (MRI) to assess the integrity of the periarticular soft tissue and flexor muscles. RESULTS: The DAA has considerable advantages, such as allowing more precise targeting during surgery, avoiding the risk of pseudoarthrosis due to the absence of a trochanteric osteotomy, preserving the abductors, and allowing an easier-to-use of intraoperative fluoroscopy due to the supine position. Besides, the use of a standard table reduces surgical time and allows assessment of limb length, hip stability, and impingement in all planes in an intraoperative dynamic range, which decreases postoperative complications. CONCLUSION: Conversion from hip fusion to THA is a rare and complex procedure. The use of DAA with a standard table and fluoroscopy helps to avoid high complications since it allows a dynamic intra-operative examination of the range of motion to rule out impingements, reduces the risk of dislocation, and allows leg lengthening verification.

Unexpected positive cultures in patients with arthrofibrosis following total hip and total knee arthroplasty.

PURPOSE: It has been suggested that low-grade infections could be the cause of arthrofibrosis. However, this hypothesis has not been conclusively proven. The aim of this study is to assess the incidence of unexpected positive cultures (UPC) in patients undergoing revision total joint arthroplasty for a diagnosis of arthrofibrosis. METHODS: A retrospective single-centre review was performed. All patients who underwent an aseptic revision due to histologically confirmed arthrofibrosis (based on the synovial-like interface membrane (SLIM) criteria) were included. The incidence of UPC was then calculated. RESULTS: A total of 147 patients were included. Of these, 100 underwent a total knee arthroplasty (TKA) procedure and 46 a total hip arthroplasty (THA) surgery. One patient had a periprosthetic joint infection and was therefore excluded. Of the 146 included patients, 6 had confirmed UPC (4.08%). The following bacteria were identified: Anaerococcus octavius, Staphylococcus epidermidis, Enterobacter cloacae, Staphylococcus hominis, Streptococcus pluranimalium, Staphylococcus pettenkoferi. CONCLUSIONS: Our results suggest that the incidence of UPC in patients with arthrofibrosis is low. It is lower than that of UPC in patients that undergo a revision for other causes. There is no proven relationship between histologically confirmed arthrofibrosis following total joint arthroplasty and prosthetic joint infection.

Unexpected positive cultures in revision total knee arthroplasty after unicompartmental knee arthroplasty.

PURPOSE: Unexpected positive cultures are defined as a single positive culture in intraoperative samples taken during revision surgery after prosthetic joint infection was preoperatively ruled out. This study aims to determine the prevalence of unexpected positive cultures (UPC) in revision total knee arthroplasty (TKA) after unicompartmental knee arthroplasty (UKA). As a secondary objective, this study aims to compare the re-intervention rate in this specific group, between UPC and non-UPC patients. The hypothesis is that the UPC prevalence in patients who undergo a revision TKA after UKA is not higher than in other TKA revision cases and this does not increase the risk of re-intervention. METHODS: This is a retrospective study where all patients who underwent a UKA revision from January 2016 to February 2023 in a high-volume arthroplasty centre, were analyzed. Unexpected positive culture prevalence in this group of patients was obtained. RESULTS: During the included period, 270 UKA revision surgeries were performed. Eight cases had at least two positive cultures and were therefore excluded. The final analysis included 262 patients. Of these, 8 (3.05%) patients presented UPCs and the isolated microorganisms were low-virulence organisms. None of the UPC patients received any treatment. No statistical differences were found between UPC and non-UPC groups in the analyzed variables. CONCLUSION: The prevalence of unexpected positive cultures in patients following revision of unicompartmental knee arthroplasty is lower than in patients who undergo a revision of total knee arthroplasty. In UKA patients a UPC does not seem to increase the risk of a re-intervention, so it can be safely ignored if ICM criteria are not met.

Cemented vs cementless stems for revision arthroplasties due to Vancouver B2 periprosthetic hip fracture.

PURPOSE: According to Vancouver classification, B2 type fractures are most often treated with removal of the loose stem and implantation of a long stem that bypasses the fracture site. However, there is a controversy about the stem fixation that should be used: cemented or cementless. Hence, this study aims to compare cemented and cementless stems in prosthetic revision due to Vancouver B2 (VB2) periprosthetic hip fracture. METHODS: A retrospective study was done including all the patients treated with stem exchange due to VB2 periprosthetic hip fracture in a tertiary hospital between 2015 and 2022. Patients were divided into two groups according to the stem fixation used: cemented or cementless. Functional outcomes, hospital stay, surgical time, complication rate, and mortality were compared between the two groups of patients. RESULTS: Of the 30 included patients, 13 (43.4%) were treated with cementless stems and 17 (56.7%) with cemented stems. There were no statistically significant differences in age, gender, anesthesia risk scale (ASA) or functional capacity prior to the intervention. Patients treated with cementless stems had a higher complication and reintervention rate than those treated with cemented stems: 62 and 45% versus 34 and 6% (p = 0.035; p = 0.010), respectively. Furthermore, in the group of cementless stems a higher proportion of non-union was found (53.8% vs. 17.6%; p = 0.037). Also, the hospital stay (33 vs. 24 days; p = 0.037) and the time to full weight-bearing (21 days vs. 9 days; p < 0.001) were longer in the cementless stem group. CONCLUSION: Cemented fixation in stem revision due to Vancouver B2 periprosthetic hip fracture could be an optimal option with faster recovery which could decrease the rate of complications and reintervention, without compromising the fracture healing and patient mortality. Thus, this option can be considered when an anatomical reduction can be obtained, especially in elderly patients with multiple comorbidities in which a less aggressive surgical option should be considered.

Vancouver B2 periprosthetic hip fractures treatment: fix or replace? A retrospective study comparing both techniques.

INTRODUCTION: Vancouver B2 periprosthetic hip fractures involve stem stability and they have been classically treated with revision surgery. Crucial factors such as age, clinical comorbidities and functional status are often neglected. The current study aims to compare clinical outcomes between patients treated with open reduction and internal fixation (ORIF) or femoral stem exchange. METHODS: This is a retrospective study that includes all Vancouver B2 periprosthetic hip fractures in a tertiary referral hospital from 2016 to 2020. Patients were divided into two groups: Group 1. Patients treated with an ORIF and Group 2. Patients treated with stem replacement. The outcomes that were compared between groups included demographic data, functional capacity, complications and mortality. RESULTS: 29 periprosthetic Vancouver B2 fractures were finally analyzed. 11 (37.9%) were treated with ORIF (Group 1) and 18 (62.1%) by stem replacement (Group 2). Surgery time (143 vs. 160 min), hemoglobin drop (1.8 vs. 2.5 g/dL) and hospital stance (25.5 vs. 29.6 days) were shorter in Group 1. According to complications, 18.2% of patients in the ORIF group had orthopedic complications compared with 44.4% in the revision group. In the revision group, 3 cases needed a two-stage revision and one of these revisions ended up with a resection arthroplasty (Girdlestone). The first-year mortality rate was 27% in Group 1 and 11% in Group 2. DISCUSSION: ORIF treatment seems to be a less aggressive and complex procedure which can lead to a faster general recovery. Revision surgery can imply a higher risk of orthopedic complications which can be severe and may require further aggressive solutions. The ORIF group mortality was similar to the proximal femur fracture rate (20-30%). In conclusion, ORIF treatment seems to be a good option especially in fragile patients with low functional demand when anatomical reduction is possible.

Total Hip Arthroplasty or Hemiarthroplasty for Hip Fracture.

BACKGROUND: Globally, hip fractures are among the top 10 causes of disability in adults. For displaced femoral neck fractures, there remains uncertainty regarding the effect of a total hip arthroplasty as compared with hemiarthroplasty. METHODS: We randomly assigned 1495 patients who were 50 years of age or older and had a displaced femoral neck fracture to undergo either total hip arthroplasty or hemiarthroplasty. All enrolled patients had been able to ambulate without the assistance of another person before the fracture occurred. The trial was conducted in 80 centers in 10 countries. The primary end point was a secondary hip procedure within 24 months of follow-up. Secondary end points included death, serious adverse events, hip-related complications, health-related quality of life, function, and overall health end points. RESULTS: The primary end point occurred in 57 of 718 patients (7.9%) who were randomly assigned to total hip arthroplasty and 60 of 723 patients (8.3%) who were randomly assigned to hemiarthroplasty (hazard ratio, 0.95; 95% confidence interval [CI], 0.64 to 1.40; P = 0.79). Hip instability or dislocation occurred in 34 patients (4.7%) assigned to total hip arthroplasty and 17 patients (2.4%) assigned to hemiarthroplasty (hazard ratio, 2.00; 99% CI, 0.97 to 4.09). Function, as measured with the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score, pain score, stiffness score, and function score, modestly favored total hip arthroplasty over hemiarthroplasty. Mortality was similar in the two treatment groups (14.3% among the patients assigned to total hip arthroplasty and 13.1% among those assigned to hemiarthroplasty, P = 0.48). Serious adverse events occurred in 300 patients (41.8%) assigned to total hip arthroplasty and in 265 patients (36.7%) assigned to hemiarthroplasty. CONCLUSIONS: Among independently ambulating patients with displaced femoral neck fractures, the incidence of secondary procedures did not differ significantly between patients who were randomly assigned to undergo total hip arthroplasty and those who were assigned to undergo hemiarthroplasty, and total hip arthroplasty provided a clinically unimportant improvement over hemiarthroplasty in function and quality of life over 24 months. (Funded by the Canadian Institutes of Health Research and others; ClinicalTrials.gov number, NCT00556842.).

Salvage hip replacement after cut-out failure of cephalomedullary nail fixation for proximal femur fractures: a case series describing the technique and results.

BACKGROUND: Cut-out failure following proximal femoral fracture fixation is a compromising complication warranting surgical treatment. We describe 24 patients with cut-out failure after cephalomedullary nail fixation managed with salvage hip replacement. METHODS: Twenty-four consecutive patients who had sustained a proximal femoral fracture from December 2009 to December 2019, were managed with cephalomedullary nail fixation and experienced a cut-out failure were reviewed retrospectively. Data on demographics, comorbidities, injury characteristics, treatment, and post-operative course were analysed. RESULTS: Among 2802 proximal femoral fractures assessed, 28 fixations failed due to cut-out, with 24/28 patients subsequently undergoing salvage hip replacement. Intertrochanteric fractures (66.7%) managed with short nails predominated (79.2%). The median tip-to-apex distance (TAD) was 19 mm, but only two fractures had a good quality of reduction. Inverse correlations were identified between patient age and the time from fixation to cut-out (r = - 0.57; p = 0.02), and between the time of nailing to failure among patients with a greater TAD (r = - 0.43; p = 0.04). Most patients were managed via cemented hemiarthroplasty (66.7%). Surgical time was longer for total hip replacements (175.4 vs. 136.8 min; p < 0.01), but no bleeding or blood transfusion requirement differences were found. Two patients had orthopaedic complications, and three patients died within the first follow-up year. CONCLUSION: In our series, 1% of the proximal femoral fractures managed with a cephalomedullary nail failed due to cut-out. Salvage hip replacement appeared to be a relatively safe and reliable procedure for managing this challenging complication in patients who typically are elderly and physically frail.

Direct anterior approach provides better functional outcomes when compared to direct lateral approach in hip hemiarthroplasty following femoral neck fracture.

PURPOSE: This study aims to compare the differences between direct anterior approach (DAA) and direct lateral approach (DLA) in hip hemiarthroplasty (HHA) after displaced femoral neck fracture (FNF) in early functional outcome, hospital length of stay, morbidity and mortality rates. METHODS: This non-interventional retrospective study, carried out at a tertiary trauma centre within the Spanish National Health System, included all patients who underwent a bipolar HHA between 1st January 2018 and 31st December 2019 performed by 2 of our hip unit surgeons. RESULTS: A total of 94 patients were included (40 in DAA group and 54 in DLA group). Median follow-up was 19.2 months (range 8-30.8 months). Postoperative degree of mobilisation showed statistically significant differences in favour of DAA group, where 35% of patients were able to walk with no assistance after surgery. DAA group had 1 day less of hospitalisation in contrast with DLA group overall (8 days vs 9 days, respectively, p < 0.05). Statistically significant differences were not detected in comparing postoperative complications, re-operations rates or 6-months mortality rate. CONCLUSION: Our study highlights the benefits of DAA for HHA after displaced FNF in terms of postoperative mobilisation degree and hospitalisation length of stay when compared to DLA.

Nosocomial infection with SARS-CoV-2 and main outcomes after surgery within an orthopaedic surgery department in a tertiary trauma centre in Spain.

AIMS: The purpose of the present study is to analyse clinical data of a series of cases who developed nosocomial infection with SARS-CoV-2 in an orthopaedic and traumatology department. PATIENTS AND METHODS: In this non-interventional retrospective study, carried out at a tertiary hospital within the Spanish National Health System, all adult patients who were admitted in the Orthopaedic Surgery and Traumatology Department between March 9th and May 4th, 2020, were included. Clinical, biological and radiological data, as well as mortality rates, were collected from hospital medical records. RESULTS: A total of 293 periods of hospitalization were analysed in 288 patients. Mean age was 66.1 years old and 57.3% were females. Nineteen patients (6.48%) met the inclusion criteria to be categorized as a nosocomial infection with SARS-CoV-2. In a comparison between patients with and without nosocomial infection, age, mortality and hospital length of stay were statistically significant (p < 0.05). The median time from admission to diagnosis of SARS-CoV-2 infection in our cohort was 16 days (6-86 days). No statistically significant differences were found in sex, living situation, reason of admission or period of admission (even if we observed that most of the nosocomial infections (78.9%) occurred in March). CONCLUSION: We have found a 6.48% of nosocomial infection with SARS-CoV-2, but with an important reduction of it after undergoing preventing protocols that included screening RT-PCR test for COVID-19. Age and hospital length stay were statistically significant risk factors for nosocomial infection with SARS-CoV-2. For the progressive restoration of the surgical activity, we recommend to correctly select the patients in elective surgery and to encourage fast-track programs and early discharge of patients with fractures.

The anterior and medial open approaches yield superior outcomes compared to the lateral and posterior open approaches in supracondylar humerus fractures in children: a systematic review and network meta-analysis.

This study aimed to perform a systematic review and network meta-analysis (NMA) to examine which open approach is superior in terms of outcomes and complications in the treatment of pediatric supracondylar humerus fractures. MEDLINE/PubMed, Embase, Web of Science, Clinicaltrials.gov, and Cochrane Library were searched from database inception to December 2022 and screened for relevant studies. Data were collected regarding patient demographics, Flynn's functional and cosmetic outcomes, and complications. Unsatisfactory Flynn's and complications were considered negative events. Comparisons of outcomes from aggregate data from each surgical approach using relative risk (RR) with a 95% confidence interval (95% CI) were performed. The NMA of overall negative events was conducted using a Bayesian hierarchical random-effects model analysis. A total of 26 studies involving 1461 patients were included; 459 (31.4%) patients underwent a closed reduction and percutaneous pinning (CRPP), 84 (5.7%) an anterior approach, 240 (16.4%) a medial, 220 (15%) a lateral, and 458 (31.3%) a posterior. The lateral and posterior approaches demonstrate a higher risk of negative event in the NMA compared to CRPP [RR = 2 (1.03, 3.85); RR = 2.63 (1.96, 3.57), respectively], anterior approach [RR = 3.33 (1.11, 10); RR = 4.35 (1.49, 12.5), respectively], and medial approach [RR = 1.82 (1.16, 2.86); RR = 2.38 (1.23, 4.76), respectively]. The medial approach resulted in a similar negative event rate compared to the anterior [RR = 1.82 (0.58, 5.88)]. The anterior and medial open approaches yield superior functional and cosmetic outcomes with fewer complications compared to the lateral and posterior.

Staged treatment of bicondylar tibial plateau fractures: influence of frame configuration and quality of reduction on outcomes.

PURPOSE: Despite evolving treatment, the surgical management of high-energy tibial plateau fractures (TPF) remains challenging, associating high rates of complications. In recent decades, staged management has emerged as an encouraging option. The main goal of our study was to evaluate the influence of bridging external fixation (EF) frame configuration and the resultant quality of reduction (QOR) on outcomes after staged-treatment of bicondylar TPF. METHODS: A retrospective review was conducted of patients with bicondylar TPF treated at our level-I trauma center using a staged-treatment protocol from January 2010 to January 2020. Data on baseline characteristics, injuries, treatments, and clinical/radiological results were collected. The QOR was evaluated on CT images after EF and on plain films after ORIF. RESULTS: Sixty-eight patients were eligible for analysis. By our criteria, QOR was good in 57.4% and 70.6% after EF and ORIF, respectively. A squared EF configuration was associated with superior EF QOR (p = 0.032), while better EF QOR was linked to improved ORIF QOR (p = 0.016). No relationship between ORIF delay and ORIF QOR was identified. Postoperative complications were documented in 19 patients. Average ROM at one-year follow-up was 114.9 ± 12.6°, and non-influenced by anterior femoral pin placement. CONCLUSIONS: Staged management of bicondylar TPF resulted in a reasonable rate of complications. A direct relationship between QORs obtained with EF and after ORIF was found. Squared frames were associated with faster and better reductions, regardless of the surgeon's background. Considering our results, we advocate for the wider use of squared EF configurations in these patients.

Mortality, perioperative complications and surgical timelines in hip fracture patients: Comparison of the Spanish with the non-Spanish Cohort of the HIP ATTACK-1 trial.

BACKGROUND: Hip fractures carry a substantial risk of complications and death. This study aimed to report the 90-day incidence of mortality, major perioperative complications and in-hospital timelines after a hip fracture in the Spanish HIP ATTACK-1 trial cohort, comparing with the non-Spanish cohort. METHODS: Prospective cohort study of Spanish patients nested in the HIP ATTACK-1 trial. The HIP ATTACK-1 was an international, randomized, controlled trial (17 countries, 69 hospitals, 7 in Spain, highest recruiting country). Patients were randomized to either accelerated surgery (goal of surgery within 6 h of diagnosis) or standard care. Participants were ≥45 years of age who presented with a low-energy hip fracture requiring surgery. RESULTS: Among 534 patients in the Spanish cohort, 69 (12.9 %) patients died at 90 days follow-up, compared to 225 (9.2 %) in the non-Spanish cohort (p = 0.009), mostly due to higher nonvascular related mortality. A composite of major postoperative complication occurred in 126 patients (23.6 %). The most common perioperative complications were myocardial injury (189 patients, 35.4 %), infection with no sepsis (86 patients, 16.1 %) and perioperative delirium (84 patients, 15.7 %); all these complication rates in Spain were significantly higher than the non-Spanish patients (29.2 % p = 0.005; 11.9 % p = 0.008 and 9.2 % p < 0.0001, respectively). Spanish cohort patients were older and had more comorbidities than the non-Spanish cohort, evidencing their greater frailty at baseline. Among Spanish patients, the median time from hip fracture diagnosis to surgery was 30.0 h (IQR 21.1-53.9) in the standard-care group, with 68.8 % of patients receiving surgery within 48 h of diagnosis. This median time was lower in the non-Spanish cohort (22.8 h, IQR 9.5-37.0), where 82.1 % of patients were operated within 48 h. CONCLUSIONS: In the HIP ATTACK-1 trial, 1 in 8 patients died 90 days after a hip fracture in Spain. The most common complication after a hip fracture was myocardial injury, followed by infection and delirium. Spanish patients had worse outcomes than non-Spanish patients. Research needs to focus on new interventions such as accelerated surgery and perioperative troponin measurement with the appropriate investment of resources, to prevent and identify early these complications with a goal of improving mortality for this high-risk population. LEVEL OF EVIDENCE: II.

Myocardial Injury in Patients with Hip Fracture: A HIP ATTACK Randomized Trial Substudy.

BACKGROUND: Myocardial injury after a hip fracture is common and has a poor prognosis. Patients with a hip fracture and myocardial injury may benefit from accelerated surgery to remove the physiological stress associated with the hip fracture. This study aimed to determine if accelerated surgery is superior to standard care in terms of the 90-day risk of death in patients with a hip fracture who presented with an elevated cardiac biomarker/enzyme measurement at hospital arrival. METHODS: The HIP fracture Accelerated surgical TreaTment And Care tracK (HIP ATTACK) trial was a randomized controlled trial designed to determine whether accelerated surgery for hip fracture was superior to standard care in reducing death or major complications. This substudy is a post-hoc analysis of 1392 patients (from the original study of 2970 patients) who had a cardiac biomarker/enzyme measurement (>99.9% had a troponin measurement and thus "troponin" is the term used throughout the paper) at hospital arrival. The primary outcome was all-cause mortality. The secondary composite outcome included all-cause mortality and non-fatal myocardial infarction, stroke, and congestive heart failure 90 days after randomization. RESULTS: Three hundred and twenty-two (23%) of the 1392 patients had troponin elevation at hospital arrival. Among the patients with troponin elevation, the median time from hip fracture diagnosis to surgery was 6 hours (interquartile range [IQR] = 5 to 13) in the accelerated surgery group and 29 hours (IQR = 19 to 52) in the standard care group. Patients with troponin elevation had a lower risk of mortality with accelerated surgery compared with standard care (17 [10%] of 163 versus 36 [23%] of 159; hazard ratio [HR] = 0.43 [95% confidence interval (CI) = 0.24 to 0.77]) and a lower risk of the secondary composite outcome (23 [14%] of 163 versus 47 [30%] of 159; HR = 0.43 [95% CI = 0.26 to 0.72]). CONCLUSIONS: One in 5 patients with a hip fracture presented with myocardial injury. Accelerated surgery resulted in a lower mortality risk than standard care for these patients; however, these findings need to be confirmed. LEVEL OF EVIDENCE: Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Clinical practice guidelines: The good, the bad, and the ugly.

Clinical practices guidelines (CPGs) play a fundamental role in improving healthcare and patients' outcomes by helping clinicians make the best evidence-based decisions for their patients in a time-efficient manner. By following the available methods and criteria to create trustworthy CPGs, panel members can develop high-quality guidelines. However, despite the improvements over the years, CPGs are still subjected to biases and limitations, with conflicts of interest being the ugliest problem GCPs must face. In this review, we discuss the main characteristics of clinical practice guidelines, their pros and cons, and the future challenges they need to overcome.

Risk of venous thromboembolism in thromboprophylaxis between aspirin and low molecular weight heparins after total hip arthroplasty or total knee arthroplasty: Systematic review and meta-analysis. / Riesgo de tromboembolismo venoso en la tromboprofilaxis entre aspirina y heparinas de bajo peso molecular tras una artroplastia total de cadera o artroplastia total de rodilla. Revisión sistemática y metaanálisis.

INTRODUCTION: The aim of this study was to evaluate the efficacy of aspirin versus low molecular weight heparins (LMWH) for the prophylaxis of venous thromboembolism (VTE), deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients undergoing total knee arthroplasty (TKA) and/or total hip arthroplasty (THA). MATERIALS AND METHODS: Systematic review and meta-analysis. Sixteen studies were selected. The risk of VTE, DVT and PE were analyzed. Mortality, risk of bleeding and surgical wound complications was also analyzed. RESULTS: 248,461 patients were included. 176,406 patients with thromboprophylaxis with LMWH and 72,055 patients with aspirin thromboprophylaxis. There were no significant differences in the risk of VTE (OR = 0.93; 95% CI: 0.69-1.26; P = .64), DVT (OR = 0.72; 95% CI: 0.43-1.20; P = .21) or PE (OR = 1.13; 95% CI: 0.86-1.49; P = .38) between both groups. No significant differences were found in mortality (P = .30), bleeding (P = .22), or complications in the surgical wound (P = .85) between both groups. These same findings were found in the sub-analysis of only randomized clinical trials (P>.05). CONCLUSIONS: No increased risk of PE, DVT, or VTE was found among patients with aspirin thromboprophylaxis versus patients with LMWH thromboprophylaxis. There was also no greater mortality, greater bleeding, or greater complications in the surgical wound found among patients with aspirin thromboprophylaxis versus patients with LMWH thromboprophylaxis.

Antimicrobials in polymethylmethacrylate: from prevention to prosthetic joint infection treatment: basic principles and risk of resistance.

BACKGROUND: Excellent revisions about antibiotic-loaded bone cement (ALBC) have been recently published. In the present article, we review the principles and limitations of local antibiotic delivery in the context of recent advances in the pathogenesis of prosthetic joint infections (PJI), with particular attention paid to the potential association between ALBC and antimicrobial resistance. MAIN BODY: Recalcitrance of PJI is related to the ability of pathogens to adapt to particular environments present in bone tissue and protect themselves from host immunity in different ways. Accordingly, delivery of high local antimicrobial concentrations using ALBC is needed. Most relevant clinical data showing the efficacy of ALBC for PJI prophylaxis and treatment are reviewed, and we dissected the limitations on the basis of the recent findings from animal models and suggested that aminoglycosides, in particular, could not be the best option. One of the major concerns associated with ALBC is the emergence of resistance because of theoretical prolonged exposure to low antibiotic concentrations. We summarize the mechanisms for the selection of resistant microorganisms, and we critically reviewed the evidence from animal models and clinical data from observational and registry studies and concluded that there is no evidence to support this association. CONCLUSION: While waiting for better evidence from well-designed clinical trials, ALBC shows a beneficial effect as a prophylaxis in arthroplasty, and to avoid the colonization of spacers used for two-stage revision in patients with PJI. Experimental models and clinical evidence suggest the need to achieve high local antimicrobial concentrations to obtain the highest prophylactic and therapeutic effect. The current evidence does not support the risk of increasing resistance with use of ALBC. In the future, it is necessary to evaluate new carriers and different antimicrobials to improve clinical outcomes.