MRI Assessment of Muscle Damage After the Posterolateral Versus Direct Anterior Approach for THA (Polada Trial). A Randomized Controlled Trial.

BACKGROUND: There is controversy in literature whether the direct anterior approach (DAA) results in less muscle damage compared with the posterolateral approach (PLA) for total hip arthroplasty. The aim of this randomized controlled trial was to assess muscle damage between these two approaches. METHODS: Forty-six patients were included. Muscle atrophy, determined with the Goutallier classification, and muscle surface of twelve muscles were analyzed on magnetic resonance imaging images made preoperatively and one year postoperatively. Differences in component placement after DAA or PLA were assessed on radiographs. Harris hip scores and Hip disability and Osteoarthritis and Outcome Score were used as functional outcomes. RESULTS: External rotator musculature was damaged in both approaches. After PLA, the obturator muscles showed significantly more atrophy and a decrease in muscle surface. After DAA, the tensor fascia latae showed an increased muscle atrophy and the psoas muscle showed a decreased muscle surface. An increase in muscle surface was seen for the rectus femoris, sartorius, and quadratus femoris after both approaches. The muscle surface of the gluteus medius and iliacus was also increased after PLA. No difference in muscle atrophy was found between the approaches for these muscles. The inclination angle of the cup in PLA was significantly higher. No differences were found in functional outcomes. CONCLUSION: Different muscle groups were affected in the two approaches. After PLA, the external rotators were more affected, whereas the tensor fascia latae and psoas muscles were more affected after DAA.

If, When, and How to Use Rifampin in Acute Staphylococcal Periprosthetic Joint Infections, a Multicentre Observational Study.

BACKGROUND: Rifampin is generally advised in the treatment of acute staphylococcal periprosthetic joint infections (PJI). However, if, when, and how to use rifampin remains a matter of debate. We evaluated the outcome of patients treated with and without rifampin, and analyzed the influence of timing, dose and co-antibiotic. METHODS: Acute staphylococcal PJIs treated with surgical debridement between 1999 and 2017, and a minimal follow-up of 1 year were evaluated. Treatment failure was defined as the need for any further surgical procedure related to infection, PJI-related death or the need for suppressive antimicrobial treatment. RESULTS: A total of 669 patients were analyzed. Treatment failure was 32.2% (131/407) in patients treated with rifampin and 54.2% (142/262) in whom rifampin was withheld (P < .001). The most prominent effect of rifampin was observed in knees (treatment failure 28.6% versus 63.9%, respectively, P < .001). The use of rifampin was an independent predictor of treatment success in the multi-variate analysis (OR 0.30, 95% CI 0.20 - 0.45). In the rifampin group, the use of a co-antibiotic other than a fluoroquinolone or clindamycin (OR 10.1, 95% CI 5.65 - 18.2) and the start of rifampin within 5 days after surgical debridement (OR 1.96, 95% CI 1.08 - 3.65) were predictors of treatment failure. The dosing of rifampin had no effect on outcome. CONCLUSIONS: Our data supports the use of rifampin in acute staphylococcal PJIs treated with surgical debridement, particularly in knees. Immediate start of rifampin after surgical debridement should probably be discouraged, but requires further investigation.

A Second Surgical Debridement for Acute Periprosthetic Joint Infections Should Not Be Discarded.

BACKGROUND: In acute periprosthetic joint infections (PJIs), a second surgical debridement (debridement, antibiotics, and implant retention [DAIR]) is generally not recommended after a failed first one. We identified the failure rate of a second DAIR and aimed to identify patients in whom an additional debridement might still be beneficial. METHODS: Patients with acute PJI of the hip or knee and treated with DAIR between 2006 and 2016 were retrospectively evaluated. A second DAIR was routinely performed provided that the soft tissue was intact. Failure of a second DAIR was described as (1) the need for additional surgical intervention to achieve infection control, (2) the need for antibiotic suppressive therapy due to persistent clinical and/or biochemical signs of infection, or (3) PJI related death. RESULTS: From the 455 cases treated with DAIR, 144 cases underwent a second debridement (34.6%). Thirty-seven cases failed (37/144, 25.7%). The implant needed to be removed in 23 cases (23/144, 16%). Positive cultures during the second DAIR (odds ratio 3.16, 95% confidence interval 1.29-7.74) and chronic renal insufficiency (odds ratio 13.6, 95% confidence interval 2.03-91.33) were independent predictors for failure in the multivariate analysis. No difference in failure was observed between persistent infection with the same microorganism and reinfection with a new microorganism (failure rate 31.6% vs 34.6%, P = .83). CONCLUSION: A second DAIR had a low failure rate in our cohort of patients and the implant could be retained in the majority of them. Therefore, a second DAIR should not be discarded in acute PJIs.

Debridement, Antibiotics, and Implant Retention Is a Viable Treatment Option for Early Periprosthetic Joint Infection Presenting More Than 4 Weeks After Index Arthroplasty.

BACKGROUND: The success of debridement, antibiotics, and implant retention (DAIR) in early periprosthetic joint infection (PJI) largely depends on the presence of a mature biofilm. At what time point DAIR should be disrecommended is unknown. This multicenter study evaluated the outcome of DAIR in relation to the time after index arthroplasty. METHODS: We retrospectively evaluated PJIs occurring within 90 days after surgery and treated with DAIR. Patients with bacteremia, arthroscopic debridements, and a follow-up <1 year were excluded. Treatment failure was defined as (1) any further surgical procedure related to infection; (2) PJI-related death; or (3) use of long-term suppressive antibiotics. RESULTS: We included 769 patients. Treatment failure occurred in 294 patients (38%) and was similar between time intervals from index arthroplasty to DAIR: the failure rate for Week 1-2 was 42% (95/226), the rate for Week 3-4 was 38% (143/378), the rate for Week 5-6 was 29% (29/100), and the rate for Week 7-12 was 42% (27/65). An exchange of modular components was performed to a lesser extent in the early post-surgical course compared with the late course (41% vs 63%, respectively; P < .001). The causative microorganisms, comorbidities, and durations of symptoms were comparable between time intervals. CONCLUSIONS: DAIR is a viable option in patients with early PJI presenting more than 4 weeks after index surgery, as long as DAIR is performed within at least 1 week after the onset of symptoms and modular components can be exchanged.

Patient satisfaction in different approaches for total hip arthroplasty.

BACKGROUND: At present, the posterolateral, the direct lateral and direct anterior approach (DAA) are the most frequently used techniques for total hip arthroplasty (THA), however there is no clear superiority of one of the approaches based on clinical outcome measures. The goal of this study is to lead the patient and the surgeon to an optimal treatment by providing them with relevant information based on patient reported outcome measures (PROMs). METHODS: Patient satisfaction and hip function one year postoperatively were investigated retrospectively in a cohort of patients who underwent hip replacement surgery by DAA on one hip and by posterolateral or direct lateral approach on the contralateral hip. Additionally, a control group who underwent the DAA bilaterally was used for comparison. RESULTS: No difference in hip function was found between the DAA and the posterolateral or direct lateral approach, measured with the Hip disability and Osteoarthritis Outcome Score (HOOS) questionnaire at least one year postoperatively to the last THA in the study group. Also in the control group no difference was found between the hips. However, the overall scores of the control group were higher, although not statistically significant, than those of the study group (p=0.055). And a majority of the study group preferred the DAA (68%), with the reasons reported being faster recovery, less sleeping disturbance and earlier mobilization. CONCLUSION: As expected, the postoperative hip function is similar, but patients' preference is not. The latter result might be true or possibly influenced by preoperative psychological factors and mental health. The DAA and the posterolateral or direct lateral approaches have shown to lead to a similar hip function, but a majority of patients subjectively prefer the DAA. LEVEL OF EVIDENCE: III.

Obese patients have higher rates of polymicrobial and Gram-negative early periprosthetic joint infections of the hip than non-obese patients.

BACKGROUND: Obese patients are more likely to develop periprosthetic joint infection (PJI) after primary total joint arthroplasty. This study compared the clinical and microbiological characteristics of non-obese, obese and severely obese patients with early PJI, in order to ultimately optimize antibiotic prophylaxis and other prevention measures for this specific patient category. METHODS: We retrospectively evaluated patients with early PJI of the hip and knee treated with debridement, antibiotics and implant retention (DAIR) between 2006 and 2016 in three Dutch hospitals. Only patients with primary arthroplasties indicated for osteoarthritis were included. Early PJI was defined as an infection that developed within 90 days after index surgery. Obesity was defined as a BMI ≥30kg/m2 and severe obesity as a BMI ≥35kg/m2. RESULTS: A total of 237 patients were analyzed, including 64 obese patients (27.0%) and 62 severely obese patients (26.2%). Compared with non-obese patients, obese patients had higher rates of polymicrobial infections (60.3% vs 33.3%, p<0.001) with more often involvement of Enterococcus species (27.0% vs 11.7%, p = 0.003). Moreover, severely obese patients had more Gram-negative infections, especially with Proteus species (12.9% vs 2.3%, p = 0.001). These results were only found in periprosthetic hip infections, comprising Gram-negative PJIs in 34.2% of severely obese patients compared with 24.7% in obese patients and 12.7% in non-obese patients (p = 0.018). CONCLUSIONS: Our results demonstrate that obese patients with early periprosthetic hip infections have higher rates of polymicrobial infections with enterococci and Gram-negative rods, which stresses the importance of improving preventive strategies in this specific patient category, by adjusting antibiotic prophylaxis regimens, improving disinfection strategies and optimizing postoperative wound care.

Flow cytometric assessment of leukocyte kinetics for the monitoring of tissue damage.

Leukocyte populations quickly respond to tissue damage, but most leukocyte kinetic studies are not based on multiparameter flow cytometry. We systematically investigated several blood leukocyte populations after controlled tissue damage. 48 patients were assigned to either an anterior or posterolateral total hip arthroplasty. Peripheral blood was collected pre-operatively and at 2 h, 24 h, 48 h, 2 and 6 weeks postoperatively and assessed by flow cytometry for absolute counts of multiple leukocyte populations using standardized EuroFlow protocols. Absolute counts of leukocyte subsets differed significantly between consecutive time points. Neutrophils increased instantly after surgery, while most leukocyte subsets initially decreased, followed by increasing cell counts until 48 h. At two weeks all leukocyte counts were restored to pre-operative counts. Immune cell kinetics upon acute tissue damage exhibit reproducible patterns, which differ between the leukocyte subsets and with "opposite kinetics" among monocyte subsets. Flow cytometric leukocyte monitoring can be used to minimally invasively monitor tissue damage.

Use of gentamicin-impregnated beads or sponges in the treatment of early acute periprosthetic joint infection: a propensity score analysis.

Objectives: Early acute periprosthetic joint infections (PJIs) treated with debridement, antibiotics and implant retention (DAIR) have failure rates ranging from 10% to 60%. We determined the efficacy of applying local gentamicin-impregnated beads and/or sponges during debridement in early PJI. Methods: Patients with early acute PJI, defined as less than 21 days of symptoms and treated with DAIR within 90 days after index surgery, were retrospectively evaluated. Early failure was defined as PJI-related death, the need for implant removal or a second DAIR or antibiotic suppressive therapy owing to persistent signs of infection, all within 60 days after initial debridement. Overall failure was defined as implant removal at any timepoint during follow-up. A 1:1 propensity score matching was performed to correct for confounding factors. Results: A total of 386 patients were included. Local gentamicin was applied in 293 patients (75.9%) and was withheld in 93 patients (24.1%). Multivariate analysis demonstrated that the use of local gentamicin was independently associated with early failure (OR = 1.97, 95% CI = 1.12-3.48). After propensity matching, early failure was 40.3% in the gentamicin group versus 26.0% in the control group (P = 0.06) and overall failure was 5.2% in the gentamicin group versus 2.6% in the control group (P = 0.40). These numbers remained when solely analysing the application of gentamicin-impregnated sponges. Conclusions: Even after propensity score matching, failure rates remained higher if local gentamicin-impregnated beads and/or sponges were administered in early acute PJI. Based on these results, their use should be discouraged.

Predicting Failure in Early Acute Prosthetic Joint Infection Treated With Debridement, Antibiotics, and Implant Retention: External Validation of the KLIC Score.

BACKGROUND: Debridement, antibiotics, and implant retention (DAIR) is a widely used treatment modality for early acute prosthetic joint infection (PJI). A preoperative risk score was previously designed for predicting DAIR failure, consisting of chronic renal failure (K), liver cirrhosis (L), index surgery (I), cemented prosthesis (C), and C-reactive protein >115 mg/L (KLIC). The aim of this study was to validate the KLIC score in an external cohort. METHODS: We retrospectively evaluated patients with early acute PJI treated with DAIR between 2006 and 2016 in 3 Dutch hospitals. Early acute PJI was defined as <21 days of symptoms and DAIR performed within 90 days after index surgery. Failure was defined as the need for (1) second DAIR, (2) implant removal, (3) suppressive antimicrobial treatment, or (4) infection-related death within 60 days after debridement. RESULTS: A total of 386 patients were included. Failure occurred in 148 patients (38.3%). Patients with KLIC scores of ≤2, 2.5-3.5, 4-5, 5.5-6.5, and ≥7 had failure rates of 27.9%, 37.1%, 49.3%, 54.5%, and 85.7%, respectively (P < .001). The receiver-operating characteristic curve showed an area under the curve of 0.64 (95% confidence interval 0.59-0.69). A KLIC score higher than 6 points showed a specificity of 97.9%. CONCLUSION: The KLIC score is a relatively good preoperative risk score for DAIR failure in patients with early acute PJI and appears to be most useful in clinical practice for patients with low or high KLIC scores.

Posterolateral vs Direct Anterior Approach in Total Hip Arthroplasty (POLADA Trial): A Randomized Controlled Trial to Assess Differences in Serum Markers.

BACKGROUND: The direct anterior approach (DAA) for total hip arthroplasty has claimed to be a true tissue-sparing minimally invasive approach that has less tissue damage and a faster recovery when compared to the posterolateral approach (PLA). The aim of this randomized controlled trial is to measure the differences in serum markers and functional outcomes between the DAA and PLA for total hip arthroplasty. METHODS: Forty-six patients were prospectively included and randomized for either the DAA (n = 23) or PLA (n = 23). All surgical procedures were performed by 3 well-trained orthopedic surgeons. The degree of tissue damage was assessed by measuring creatine kinase (CK) and C-reactive protein levels (CRP) preoperatively and 2 hours, 1 day, 2 weeks, and 6 weeks postoperatively. Generalized linear mixed models analyses were used to assess differences between serum markers over time; correction for possible confounding factors was performed. The Hip disability and Osteoarthritis Outcome Score and the Harris Hip Score were assessed preoperatively and 6 weeks postoperatively. RESULTS: There were no differences in patient demographics. The DAA had a longer operative time (P = .001). CK and CRP levels increased postoperatively, but no significant differences between the groups were found on any of the time points. Functional outcomes were also similar in both approaches. CONCLUSION: No difference in tissue damage measured with serum markers CK and CRP were found between the DAA and PLA for total hip arthroplasty.

The development of a comprehensive multidisciplinary care pathway for patients with a hip fracture: design and results of a clinical trial.

BACKGROUND: Hip fractures frequently occur in older persons and severely decrease life expectancy and independence. Several care pathways have been developed to lower the risk of negative outcomes but most pathways are limited to only one aspect of care. The aim of this study was therefore to develop a comprehensive care pathway for older persons with a hip fracture and to conduct a preliminary analysis of its effect. METHODS: A comprehensive multidisciplinary care pathway for patients aged 60 years or older with a hip fracture was developed by a multidisciplinary team. The new care pathway was evaluated in a clinical trial with historical controls. The data of the intervention group were collected prospectively. The intervention group included all patients with a hip fracture who were admitted to University Medical Center Groningen between 1 July 2009 and 1 July 2011. The data of the control group were collected retrospectively. The control group comprised all patients with a hip fracture who were admitted between 1 January 2006 and 1 January 2008. The groups were compared with the independent sample t-test, the Mann-Whitney U-test or the Chi-squared test (Phi test). The effect of the intervention on fasting time and length of stay was adjusted by linear regression analysis for differences between the intervention and control group. RESULTS: The intervention group included 256 persons (women, 68%; mean age (SD), 78 (9) years) and the control group 145 persons (women, 72%; mean age (SD), 80 (10) years). Median preoperative fasting time and median length of hospital stay were significantly lower in the intervention group: 9 vs. 17 hours (p < 0.001), and 7 vs. 11 days (p < 0.001), respectively. A similar result was found after adjustment for age, gender, living condition and American Society of Anesthesiologists (ASA) classification. In-hospital mortality was also lower in the intervention group: 2% vs. 6% (p < 0.05). There were no statistically significant differences in other outcome measures. CONCLUSIONS: The new comprehensive care pathway was associated with a significant decrease in preoperative fasting time and length of hospital stay.

[A woman with multiple masses on her left hand]. / Een vrouw met multipele zwellingen aan de linker hand.

We describe a 66-year-old woman who presented with firm masses on her left hand, which had recently increased in size, and multiple haemangiomas. A diagnosis of Maffucci syndrome was established. Renewed growth of enchondromas during adulthood is suspicious for malignant transformation. Therefore, curettage with adjuvant fenolisation was performed in our patient. Clinical and radiological follow-up was required concerning local recurrence.

Transfer of bacteria between biomaterials surfaces in the operating room--an experimental study.

Bacterial adhesion to and transfer between surfaces is a complicated process. With regard to the success of biomaterials implants, studies on bacterial adhesion and transfer should not be confined to biomaterials surfaces in the human body, but also encompass surfaces in the operating room, where the origin of many biomaterials related infections is found. The purpose of this study was to quantify the transfer of Staphylococcus aureus, Staphylococcus epidermidis, and Propionibacterium acnes from one operating room material to another, while accounting for surface hydrophobicity and roughness, moistness and application of friction during transfer. The tested operating room materials were gloves, broaches (orthopaedic drills), theatre gowns, and light handles. As a possible clinical intervention method to prevent transfer, it was investigated whether dipping the gloves in a chlorhexidine splash-basin affected the viability of the transferred bacteria. Transfer (moist and without friction) was demonstrated to some extent with all bacterial strains and with every material, ranging from 17% to 71%, and was influenced by the bacterial strain, moistness of the inoculum, the application of friction, and the characteristics of both the donating and the receiving surface. Dipping the glove material in 4% or 0.4% chlorhexidine solutions killed all bacteria present, regardless of whether surfaces were dried or moist and thus prevented transfer.

Intraoperative contamination influences wound discharge and periprosthetic infection.

Intraoperative bacterial contamination increases risk for postoperative wound-healing problems and periprosthetic infection, but to what extent remains unclear. We asked whether bacterial contamination of the instruments and bone during primary prosthesis insertion was associated with prolonged wound discharge and subsequent periprosthetic infection. During 100 total hip arthroplasties, four intraoperative cultures were taken from the instruments and two portions of removed bone. Postoperatively, the duration of wound discharge was monitored, with Day 5 as the cut-off point. All patients were followed for 2 years to determine whether periprosthetic infection occurred. Bacterial contamination occurred in 36 operative procedures (36%). We found an association between intraoperative contamination and prolonged wound discharge, with a relative risk of 2.5. The culturing of removed bone had a positive predictive value of 81% to 90%. Other factors associated with prolonged wound discharge were rheumatoid arthritis (relative risk, 6.4), use of cement (relative risk, 1.6), and increased blood loss (relative risk, 1.5).