Clinical results and complications of a two-stage procedure in hip infection using preformed antibiotic-loaded cement spacers.

Antibiotic-loaded cement spacers are used in two- stage hip replacement. The aim of our study was to compare our results using a Spacer-G with previous results reported in the literature. From June 2002 to April 2010, all patients treated with a two-stage revision were retrospectively reviewed. On the basis of the results of the first-stage procedure, 52 patients underwent the second stage, six developed a dislocation, in eight the spacer was maintained, and five patients developed an acute infection of the spacer or the infection was not resolved. With regard to the second-stage procedure the revision was successful in 44 patients, a re-infection developed in four patients and the definitive prosthesis presented a mechanical complication in four more. The literature results reported that 97.5% of the spacers were reimplanted, although 12.09% of them developed a dislocation. Surgeons must assess several aspects so as to avoid mechanical complications like dislocation and re- infections during the two stages of the procedure.

Early clinical and radiological outcomes for the Taperloc Complete Microplasty stem.

The use of short stem designs in total hip arthroplasty is not a new concept, but its popularity has increased as a bone-sparing alternative to traditional stems. This study analyzed the midterm clinical and radiological results of the Taperloc Complete Microplasty stem (Zimmer Biomet® Warsaw, IN, USA). A total of 32 patients (20 men and 12 women) were retrospectively documented and received 40 stems (eight bilateral). The median patient age was 50 years (interquartile range 43-58) at the time of surgery. The median follow-up was 36.5 months (interquartile range 26.75-50.25). Indication for total hip arthroplasty was osteoarthritis (62.5% of patients), avascular necrosis (25%), and developmental dysplasia of the hip (12.5%). The Merle d'Aubigné score improved from a mean 11.5 preoperatively to a mean 17.5 at the latest follow-up. During X-ray assessment, we observed one subsidence of the stem (3 mm) and four cases of varus malalignment without clinical consequences. No cases of osteolysis were reported, and no stems were revised. According to our results, this short tapered stem shows a good early-term outcome. Prospective results and a longer follow-up are needed to assess the long-term survival of this stem fully.

Usefulness of Culturing the Periprosthetic Membrane or Neosynovium for the Diagnosis of Infection During Hip and Knee Revision Arthroplasty.

INTRODUCTION: Identification of microorganisms is critical for correct management of an infected arthroplasty. Our hypothesis is that the culture yield depends on the location around the prosthesis from which samples are obtained. METHODS: This prospective study included 298 revisions of the hip (123) and knee (175). We compared the yield of the intraoperative samples obtained, which included synovial fluid (two), neosynovium (two), and periprosthetic membrane (two). RESULTS: Cultures were positive in 28 cases, in which 15 had the same diagnosis considering either the neosynovium or the membrane, and there were 3 cases in which the infection could have been diagnosed only by considering the combination of both. In all, there were 8 cases in which the infection might have been misdiagnosed unless considering a combination of both solid tissue samples (P = 0.004). CONCLUSIONS: The yields of the periprosthetic membrane and neosynovium do not differ significantly, and we recommend considering a combination of both. LEVEL OF EVIDENCE: Diagnostic Level II.

One- and two-stage surgical revision of peri-prosthetic joint infection of the hip: a pooled individual participant data analysis of 44 cohort studies.

One-stage and two-stage revision strategies are the two main options for treating established chronic peri-prosthetic joint infection (PJI) of the hip; however, there is uncertainty regarding which is the best treatment option. We aimed to compare the risk of re-infection between the two revision strategies using pooled individual participant data (IPD). Observational cohort studies with PJI of the hip treated exclusively by one- or two-stage revision and reporting re-infection outcomes were retrieved by searching MEDLINE, EMBASE, Web of Science, The Cochrane Library, and the WHO International Clinical Trials Registry Platform; as well as email contact with investigators. We analysed IPD of 1856 participants with PJI of the hip from 44 cohorts across four continents. The primary outcome was re-infection (recurrence of infection by the same organism(s) and/or re-infection with a new organism(s)). Hazard ratios (HRs) for re-infection were calculated using Cox proportional frailty hazards models. After a median follow-up of 3.7 years, 222 re-infections were recorded. Re-infection rates per 1000 person-years of follow-up were 16.8 (95% CI 13.6-20.7) and 32.3 (95% CI 27.3-38.3) for one-stage and two-stage strategies respectively. The age- and sex-adjusted HR of re-infection for two-stage revision was 1.70 (0.58-5.00) when compared with one-stage revision. The association remained consistently absent after further adjustment for potential confounders. The HRs did not vary importantly in clinically relevant subgroups. Analysis of pooled individual patient data suggest that a one-stage revision strategy may be as effective as a two-stage revision strategy in treating PJI of the hip.

Preliminary Results After Changing From Two-Stage to One-Stage Revision Arthroplasty Protocol Using Cementless Arthroplasty for Chronic Infected Hip Replacements.

BACKGROUND: The objective of our study is to evaluate our preliminary results after changing from a 2-stage revision arthroplasty protocol to a 1-stage revision arthroplasty protocol using cementless arthroplasty for all patients with chronic infected hip replacements. METHODS: Prospective study of all hip arthroplasties that were diagnosed with chronic infection and were treated using the 1-stage revision without taking into account the traditional criteria used to determine the use of a 1-stage revision was conducted. There were 2 main variables evaluated: infection control and costs. The definitive diagnosis of infection of the revision was determined using the criteria proposed by the Musculoskeletal Infection Society. The costs were calculated using average cost in USD, excluding social expenses, as described by Klouche (2010) for 1-stage or 2-stage revisions. RESULTS: Nineteen patients were included in the study and the infection was controlled in 18 patients. The total economic savings for our hospital for these 19 patients was 391.609 USD. CONCLUSION: This clinical success has led to an important change in our hospital in treating chronic infected hip replacements and an important cost reduction from an economic point of view.

Moxifloxacin plus rifampin as an alternative for levofloxacin plus rifampin in the treatment of a prosthetic joint infection with Staphylococcus aureus.

OBJECTIVES: The combination of a fluoroquinolone with rifampin is one of the cornerstones in the treatment of prosthetic joint infections (PJI) caused by staphylococci. Moxifloxacin is highly active against methicillin-susceptible Staphylococcus aureus (MSSA) and, therefore, is an attractive agent to use. However, several studies reported a lowering in serum moxifloxacin levels when combined with rifampin. The clinical relevance remains unclear. We determined the outcome of patients with early acute PJI caused by MSSA treated with either moxifloxacin/rifampin or levofloxacin/rifampin. METHODS: Medical files of patients treated with moxifloxacin/rifampin (University Medical Centre Groningen) or levofloxacin/rifampin (Hospital Clinic Barcelona) were retrospectively reviewed (2005-2015). Treatment failure was defined as the need for revision surgery and/or suppressive therapy, death by infection or a relapse of infection during follow-up. RESULTS: Differences in baseline characteristics between the two cohorts were observed, but prognostic parameters for failure, as defined by the KLIC-score (Kidney failure, Liver cirrhosis, Index surgery, C-reactive protein and Cemented prosthesis), were similar in the two groups (2.9 [1.5 SD] for the moxifloxacin group vs. 2.2 [1.2 SD] for the levofloxacin group [P = 0.16]). With a mean follow-up of 50 months (36 SD) in the moxifloxacin group, and 67 months (50 SD) in the levofloxacin group (P = 0.36), treatment was successful in 89% vs. 87.5%, respectively (P = 0.89). None of the failures in the moxifloxacin group were due to rifampin- or moxifloxacin-resistant S. aureus strains. CONCLUSION: Our data indicate that moxifloxacin combined with rifampin is as clinically effective as levofloxacin/rifampin for early acute PJI caused by MSSA.

Hypertrophy of the tensor fascia lata muscle as a complication of total hip arthroplasty.

INTRODUCTION: Hypertrophy of the tensor fascia lata muscle (HTFLM) is a rare complication after total hip arthroplasty (THA) and is a potential source of pain, palpable mass, or both. MATERIALS AND METHODS: We retrospectively analyzed 1285 primary THAs and 482 THA revisions (THAR) performed at our center from 2008 to 2014. Among these, five patients had HTFLM (average age 68.8 years). The type of surgery and symptoms were evaluated, as were imaging studies (CT or MRI) of both hips (10 hips), and functional outcomes with the Merle d'Aubigné score. RESULTS: The suspected diagnosis was established at an average of 30.2 months after surgery. Four cases occurred after THA and one case after THAR. A modified Hardinge approach was used in four cases and a Röttinger approach in one case. Two cases had pain and palpable mass in the trochanteric region and three cases only pain. The asymmetric HTFLM of the THA side against the nonsurgical side was confirmed by measuring the cross section of the tensor fascia lata muscle on imaging. The sartorius muscle was measured for reference in each case. The Merle d'Aubigne scale had a mean value of 16.6 (range 13-18) at 38 months after the procedure. CONCLUSIONS: HTFLM after THA is a benign condition that could be mistaken for a tumor when presenting as a palpable mass. We propose that it should be considered in the differential diagnosis of pain in the lateral aspect of hips that have previously undergone THA.

The use of a "rim cutter" device and a flanged cup for improving the mantle of the acetabular component of a cemented Exeter total hip arthroplasty.

A retrospective study was performed to evaluate the cement mantle in two groups of patients treated with the acetabular components of cemented Exeter total hip arthroplasties (THAs). Two groups of 20 patients were compared: Group 1 received non-flanged acetabular cemented cups (Contemporary, Stryker) and Group 2 received flanged acetabular cemented cups (X3 Rim Fit, Stryker). Cups in Group 2 were implanted after using a rim cutter device. Group 2 showed better penetration of cement in zone 1 (10.76 mm compared with 2.93 mm; p = 0.008) and a thicker cement mantle in zone 1 (3.57 mm compared with 2.89 mm; p = 0.04). More cups in Group 2 had a cement mantle thickness less than 3 mm (30 % in Group 1 compared with 70 % in Group 2; p = 0.0039). No other radiological differences were observed. These results favor the use of a rim cutter device and flanged cup to improve the cement mantle for the acetabular components of cemented Exeter THAs. However, the improvements were less than expected. In view of the results of previous studies, further research is therefore needed to assess the value of this approach in improving the acetabular cement mantle.

Trabecular TitaniumTM cups and augments in revision total hip arthroplasty: clinical results, radiology and survival outcomes.

BACKGROUND: Large acetabular defects remain a challenge in hip revision arthroplasty. Experience with Trabecular Titanium™ (TT) cups (Limacorporate S.p.a.) has not been widely reported. Therefore, we assessed the survivorship and clinical and radiological outcomes of patients receiving TT cups, with or without supplementary trabecular titanium hemispherical modules for acetabular reconstruction, in primary and revision total hip arthroplasty (THA). METHODS: Between January 2009 and July 2014, we performed 67 revisions and 5 primary THAs using TT cups in 69 patients. To achieve stability and/or restore the hip's centre of rotation, hemispherical modules were used in 17 cases based on preoperative templating and/or intraoperative findings. Mean follow-up was 30.5 months. Acetabular bone defects were classified according to the Paprosky classification. Survivorship, functional outcomes (Merle d'Aubigné) and radiological outcomes were analysed. RESULTS: 8 patients underwent cup revision: 2 for loosening, 3 for infection, and 3 for hip dislocation. The remaining cases did not present radiological signs of loosening. None of the cases with Paprosky type I classifications needed revision, while 4 with type II and 4 with type III needed revision (p = 0.028). The respective mean values for pain, walking, and range of motion (Merle d'Aubigné scores ± standard deviation) were 3.6 ± 1.4, 3.7 ± 0.7, and 3.8 ± 0.6 preoperatively, and 5.7 ± 0.7, 5.3 ± 0.7, and 5.6 ± 0.7 at the latest follow-up (p<0.001). CONCLUSIONS: In the short term, results with TT cups appear to be encouraging, with satisfactory survival rates for both simple and complex cases.

Incidence and Risk Factors for Infection When Teicoplanin Is Included for Prophylaxis in Patients with Hip Fracture.

BACKGROUND: Surgical site infection (SSI) rate after surgery for hip fracture is about 4%. The aim of the present study was to review the efficacy of dual prophylaxis using teicoplanin plus cefuroxime and risk factors for SSI. PATIENTS: Operations for hip fracture from 2012 to 2013 were retrospectively reviewed. Relevant information was gathered: Demographics, comorbidities, ASA score, laterality, type of fracture, type of surgery, d from admission to surgery, length of surgery, hemoglobin value at admission, urinary or respiratory infections, and the need for pre-operative, intra-operative, and post-operative red blood cell (RBC) transfusion. Prophylaxis consisted of cefuroxime and teicoplanin during the induction of anesthesia. U.S. Centers for Disease Control and Prevention (CDC) criteria for superficial and deep SSI were applied. Univariate and multivariable analysis were performed. RESULTS: Six hundred fifty-seven patients were included in the study. Thirteen (2.0%) SSI were identified, six superficial (0.9%), and seven deep (1.1%). Staphylococcus aureus was isolated in two infections (one superficial and one deep). The SSI rate was 2.4% in intra-medullary nails (n = 334), 1.4% in prostheses (n = 211), and 1.8% in other synthesis (n = 112). Parameters independently associated with SSI were: Intra-operative RBC transfusion (OR: 11.6, p = 0.002), length of surgery >120 min (OR: 4.5, p = 0.02), and having a urinary infection (OR: 4.28, p = 0.02). CONCLUSION: Dual prophylaxis including cefuroxime and teicoplanin was associated with a 2% rate of SSI. Staphylococcus aureus caused only two SSIs. Reducing SSI is of utmost importance for patients' quality of life and to avoid additional cost of surgical procedures. Therefore, more experience with dual prophylaxis is needed to confirm our results.

Assessment of Patients with a DePuy ASR Metal-on-Metal Hip Replacement: Results of Applying the Guidelines of the Spanish Society of Hip Surgery in a Tertiary Referral Hospital.

The prognosis associated with the DePuy ASR hip cup is poor and varies according to the series. This implant was withdrawn from use in 2010 and all patients needed to be assessed. We present the results of the assessment of our patients treated with this device, according to the Spanish Society of Hip Surgery (SECCA) algorithm published in 2011. This retrospective study evaluates 83 consecutive ASR cups, followed up at a mean of 2.9 years. Serum levels of chromium and cobalt, as well as the acetabular abduction angle, were determined in order to assess their possible correlation with failure, defined as the need for revision surgery. The mean Harris Hip Score was 83.2 (range 42-97). Eight arthroplasties (13.3%) required revision due to persistent pain and/or elevated serum levels of chromium/cobalt. All the cups had a correct abduction angle, and there was no correlation between elevated serum levels of metal ions and implant failure. Since two previous ASR implants were exchanged previously to the recall, the revision rate for ASR cups in our centre is 18.2% at 2.9 years.

One-stage revision arthroplasty using cementless stem for infected hip arthroplasties.

The objective of this retrospective study was to evaluate our results with one-stage revision using cementless femoral stem for infected hip arthroplasties. Twenty-four patients were included in the study. The acetabular component was cemented in 9 cases. In 2 patients a structured bone allograft was necessary to fill an acetabular defect. After a mean follow-up of 44.6 months, 23 patients showed no signs of infection (95.8%), the mean functional response according to the Merle d'Aubigné scale was 13.8 and the mean Harris Hip Score was 65.4. One-stage revision hip arthroplasty using cementless femoral stem was associated with a high success rate.

[Psoas abscess associated with hip arthroplasty infection]. / Absceso de psoas asociado a infección de una artroplastia de cadera.

INTRODUCTION: Psoas abscess associated with hip arthroplasty infection is a rare entity. The aim of this report was to review our experience. MATERIAL AND METHODS: Patients with computerized tomography (CT) diagnosis of psoas abscess associated with a hip arthroplasty infection from 2004 to 2009 were retrospectively reviewed. Demographics, microbiological data, CT results and outcome of each patient were recorded. RESULTS: Seven patients out of 214 evaluated by CT due to hip infection suspected were identified. Three women and 4 men, with a mean age of 69 years (range 46-89). Mean abscess diameter was of 62 x 47 mm. In all cases, a direct communication between abscess and prosthesis was observed. The most commonly isolated microorganisms were grampositive cocci. All patients were treated with two-stage revision surgery. After a mean follow-up of 65 months (28-113), six patients were in remission. CONCLUSIONS: The use of CT in the study of suspected infection of a hip arthroplasty identified a psoas abscess in 7 cases out of 214 evaluated. Patients treated with two-stage revision surgery and large debridement was associated with a good clinical outcome.

Usefulness of histology for predicting infection at the time of hip revision for the treatment of Vancouver B2 periprosthetic fractures.

When facing a Vancouver B2 periprosthetic fracture, the most recommended treatment is the prosthesis replacement. Current tests do not provide enough reliability to identify whether the fracture has been produced on a septic or an aseptic loosened prosthesis. Our aim was to evaluate the usefulness of the histology for the diagnosis of infection in these cases. A total of 11 hip revision procedures were performed (mean age: 78.1 years, 8 women and 3 men). Sensitivity, specificity, positive predictive value and negative predictive value of the histology were 100%, 55.5%, 33.3% and 100% respectively. Of the six patients presenting with a positive histology, four of them had negative cultures (66.6% of false positives). Our results suggest that periprosthetic fractures are a cause of false-positive histology results for the diagnosis of infection during revision of a hip prosthesis for the treatment of Vancouver B2 periprosthetic fractures.

Prosthetic joint infections due to methicillin-resistant and methicillin-susceptible staphylococci treated with open debridement and retention of the prosthesis.

OBJECTIVES: To compare the specific characteristics, the outcome and the predictors of failure of prosthetic joint infections (PJI) due to methicillin-resistant (MRS) and methicillin- susceptible staphylococci (MSS) treated with open debridement and retention of the implant. MATERIAL AND METHODS: PJI due to MRS or MRS prospectively registered in a database from 1999 to 2009 were retrospectively reviewed. RESULTS: During the study period, 96 patients met the inclusion criteria of the study. The mean follow-up period was 3.9 years and at least 2 years in all patients. The failure rate was 25%. The only variable significantly associated with failure in the global cohort was polymicrobial infection (59.3% vs. 40.7%, p=0.036). Thirty-four (35.4%) patients had an infection due to MRS and 62 (63.6%) due to MSS. Among MSS infections, 95.2% corresponded to primary arthroplasties while 29.4% of PJI due to MRS were after revision arthroplasties (p=0.001). CRP was significantly higher in PJI due to MSS (5.2 mg/dl vs 9.1 mg/dL, p=0.02).The failure rate (20% vs 27%, p=0.62) was very similar in MSS and MRS groups. CONCLUSION: PJI due to MRS were mainly coagulase-negative staphylococci, more frequent after revision arthroplasties, had a lower inflammatory response, and had a similar failure rate than MSS infections.

Traumatic atlanto-occipital dislocation: a case report.

We report a 30-year-old man with atlanto-occipital dislocation after a traffic accident. Diagnosis was based on radiography, computed tomography, and magnetic resonance imaging. Owing to the critical conditions that did not fulfil advanced trauma and life support protocols, surgical treatment was deferred, and the patient died 10 hours later.

Long-term results of acute prosthetic joint infection treated with debridement and prosthesis retention: a case-control study.

PURPOSES: To evaluate the long-term outcome (at least 4 years) of patients who underwent a surgical debridement due to an acute prosthetic joint infection (PJI) and to compare them with a control group that did not have an acute septic complication. METHODS: From January 1999 to December 2007, 61 patients with an acute PJI in remission after 2 years of follow-up (cases) were retrospectively reviewed and compared with a control group (2:1) without an acute PJI matched by age, year of arthroplasty, and type of prosthesis. Septic and aseptic complications of each group were gathered and compared using a chi-square test. A two-tailed p value <0.05 was considered statistically significant. RESULTS: Out of 183 patients, 4 cases and 2 controls were excluded due to death or lost to follow up; 113 (63.8%) were females and 109 (61.5%) had a knee replacement. The mean age and time of followup were 68.3 and 6.4 years, respectively. There were no statistically significant differences between cases and controls in the percentage of late septic or aseptic loosening. However, the late relapse rate in patients with acute PJI caused by S. aureus, was 12.5% (2 out of 16) and there was a trend towards significance when compared with the rest of the cohort (3.3%, p = 0.09). Aseptic late complications were more frequent in GN-cases (10.7%) than in the other groups (3.4% in GP-cases and 5% in controls) but this difference was not statistically significant (p = 0.19). CONCLUSIONS: In conclusion, although analyzing all late complications together, patients with an acute PJI have a similar long-term outcome in comparison with controls; patients with an acute PJI due to S. aureus had a higher late relapse rate; and GN-cases developed an aseptic loosening more ?frequently. In the future, it is necessary to evaluate larger series to confirm our results.

Efficacy of debridement in hematogenous and early post-surgical prosthetic joint infections.

PURPOSES: To review patients with a hematogenous and early post-surgical prosthetic joint infection (PJI) due to S. aureus treated with debridement and retention of the implant and to compare their clinical characteristics and outcome. METHODS: From January 2000 all patients with a prosthetic joint infection treated in a single-center were prospectively registered and followed-up. All potentially variables associated with outcome were recorded. For the present study, cases with a hematogenous or early post-surgical PJI due to S. aureus treated with debridement and at least 2 years of follow-up were reviewed. Cox regression model to identify factors associated with outcome were applied. RESULTS: 12 hematogenous and 53 early post-surgical PJI due to S. aureus were included. Number of patients presenting with fever, leucocyte count, C-reactive protein concentration, and the number of bacteremic patients were significantly higher in hematogenous infections while the number of polymicrobial infections was lower in hematogenous than in early post-surgical infections. The global failure rate in hematogenous and early post-surgical PJI was 58.7% and 24.5%, respectively (p=0.02). The Cox regression model identified hematogenous infections (OR: 2.57, CI95%: 1.02-6.51, p=0.04) and the need of a second debridement (OR: 4.61, CI95%: 1.86-11.4, p=0.001) as independent predictors of failure. CONCLUSION: Hematogenous infections were monomicrobial and had more severe symptoms and signs of infection than early post-surgical PJI. Hematogenous PJI due to S. aureus, using debridement with implant retention, had a worse outcome than early post-surgical infections.

Relationship between the degree of osteolysis and cultures obtained by sonication of the prostheses in patients with aseptic loosening of a hip or knee arthroplasty.

INTRODUCTION: The pathogenesis of prosthesis loosening is not well understood. The aim of our study was to sonicate components of joint prostheses removed due to aseptic loosening, culture the sonicate fluid, and to correlate these results with the degree of radiological osteolysis. METHODS: From January 2008 to June 2009 all consecutive patients who underwent a revision of hip or knee prosthesis due to aseptic loosening were included in the study. Aseptic loosening was established when the patient had radiological signs of loosening without symptoms or signs of infection. The diagnosis was confirmed when histology was negative, and ≥ 5 out of 6 standard cultures of periprosthetic tissue were negative. Bone lysis was measured according to the Paprosky or Engh classifications without knowing the result of sonication cultures. Removed components were placed in sterile bags and immediately transported to the microbiology laboratory and sonicated. Sonicate fluid was cultured and the results were correlated with the degree of bone lysis. The proportion of components with positive sonication culture according to the bone lysis classification was compared using χ(2) test. RESULTS: A total of 52 patients were included and 123 components were sonicated. In 30 patients at least 1 sonicated component was positive (57.7%) and 44 out of 123 (35.8%) components were positive. The proportion of positive sonication cultures was significantly higher in the group of components with a higher degree of bone lysis of 3 (76.5%) than in those with lower degrees (33.9% for 1 and 24% for 2) (χ(2) test, p = 0.0004). CONCLUSIONS: Sonication cultures were positive in 57% of patients who underwent revision arthroplasty for aseptic loosening. The percentage of positive sonication cultures was significantly higher in patients with severe osteolysis. LEVEL OF EVIDENCE: level I of Prognostic Studies-Investigating the Effect of a Patient Characteristic on the Outcome of Disease.