Intra-operative bacterial contamination : control and consequences

Een combinatie van gedragsmaatregelen en een beter luchtinblaassysteem in de operatiekamer leidt tot een afname van het aantal bacteriën bij plaatsing van een knie- of heupprothese. Hierdoor neemt de kans af op infectie van de prothese en op problemen met wondgenezing na de operatie. Dit blijkt uit onderzoek van Bas Knobben, uitgevoerd bij de afdeling Orthopedie en de vakgroep Biomedical Engineering van het Universitair Medisch Centrum Groningen. Deze bevindingen kunnen ertoe bijdragen dat gewrichtsprothesen minder vaak infecteren en vervangen moeten worden. Hij promoveert op 26 april 2006 op zijn onderzoek aan de Rijksuniversiteit Groningen. In elke operatiekamer kunnen ondanks strenge hygiënische maatregelen bacteriën voorkomen die een mogelijk risico vormen voor infectie van prothesen en problemen met wondgenezing na de operatie. Tot nu toe was de omvang hiervan onduidelijk. Uit het onderzoek van Knobben blijkt dat bij 36 procent van de plaatsingen van heupprothesen bacteriën aanwezig waren op het instrumentarium en op verwijderde botsnippers bij het inbrengen van de prothesen. Ook bleek er een verband te zijn tussen het vóórkomen van deze bacteriën en het optreden van verstoorde wondgenezing en infectie van de prothesen. Gedragsmaatregelen Knobben onderzocht of gedrags- en technische maatregelen, aanvullend op de gebruikelijke hygiënerichtlijnen, de kans op bacteriële besmetting tijdens de operatie verkleinen. Uit zijn onderzoek blijkt dat de combinatie van deze maatregelen in een operatiekamer de kans op aanwezigheid van bacteriën deed afnemen van 34 procent naar 8 procent. Tegelijk nam de kans op infectie van prothesen, verstoorde wondgenezing en wondinfectie beduidend af. De gedragsmaatregelen die onder andere werden genomen, zijn het beperken van het spreken en het in- en uitlopen van de operatiekamer door het operatiekamerpersoneel, het gecontroleerd bewegen, het juiste gebruik van het neus-/mondkapje en een beter gebruik van het gebied onder de luchtstroom. Een van de technische maatregelen betrof het gebruik van een beter luchtinblaassysteem (laminaire airflow). Hierbij vindt een constante aanvoer van schone lucht plaats boven het operatiegebied en worden bacteriën via verticale luchtstromen afgevoerd. Kosteneffectief Met dit onderzoek toont Knobben aan dat gedragsmaatregelen en een beter luchtinblaassysteem in de operatiekamer infecties van prothesen en problemen met wondgenezing kunnen voorkomen. De maatregelen zijn bovendien kosteneffectief: de gemiddelde totale kosten per patiënt met een eerste (primaire) prothese zonder infectie zijn ongeveer € 15.000, zo’n 3,5 keer lager dan die van een patiënt met een geïnfecteerde prothese (ongeveer € 52.000). De resultaten van dit proefschrift hebben ertoe geleid dat het Universitair Medisch Centrum Groningen de aanvullende gedrags- en technische maatregelen toepast bij het plaatsen van prothesen. Verdubbeling In Nederland zijn in 2004 ongeveer 25.000 heup- en 20.000 knieprothesen geplaatst. De belangrijkste indicatie voor het plaatsen hiervan is gewrichtsslijtage. De verwachting is dat door vergrijzing het aantal mensen dat in aanmerking komt voor deze operaties de komende twintig jaar zal verdubbelen. Bij ongeveer één tot vier procent van de patiënten treedt na plaatsing een bacteriële infectie op.

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

The design of a randomised controlled trial to evaluate the (cost-) effectiveness of the posterolateral versus the direct anterior approach for THA (POLADA - trial)

Background: Total hip arthroplasty (THA) is one of the most successful orthopaedic procedures. Because of the increasing number of THAs, a growing demand for faster recovery and a greater emphasis on cost-effectiveness, minimally invasive THAs have been introduced in the last decades. The direct anterior approach is a minimally invasive, tissue-sparing approach in which intermuscular planes are used. Theoretically, this approach should result in a faster recovery of physical functioning and higher health-related quality of life. Methods/design: A randomised controlled trial will be performed. Patients will be randomly allocated to undergo THA by means of the anterior or posterolateral approach. Both the intervention and control group will consist of two subgroups: 1) patients with a good bone stock who will receive an uncemented femoral stem, and 2) patients with a poor bone stock who will receive a cemented femoral stem. Patients between 18 and 90 years with primary or secondary osteoarthritis will be included. Physical functioning and health-related quality of life will be assessed by means of questionnaires. Additionally, performance based tests will be performed to objectively assess the physical functioning. Cost-effectiveness will be assessed by obtaining data on medical costs in and outside the hospital and other nonmedical costs. Measurements will take place preoperatively, two and six weeks, three months and one year postoperatively. Discussion: There is some evidence that the anterior approach results in reduced tissue damage and faster recovery in the direct postoperative period, compared to the posterolateral approach. However, there is still a lack of well-designed studies that have confirmed the better outcomes and cost-effectiveness of the anterior approach. Therefore, the purpose of this study is to assess the physical functioning, health related quality of life and the cost-effectiveness of the anterior approach, compared to the conventional posterolateral approach

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

A protocol for periprosthetic joint infections from the Northern Infection Network for Joint Arthroplasty (NINJA) in the Netherlands

Periprosthetic joint infection (PJI) is a devastating complication of joint arthroplasty surgery. Treatment success depends on accurate diagnostics, adequate surgical experience and interdisciplinary consultation between orthopedic surgeons, plastic surgeons, infectious disease specialists and medical microbiologists. For this purpose, we initiated the Northern Infection Network for Joint Arthroplasty (NINJA) in the Netherlands in 2014. The establishment of a mutual diagnostic and treatment protocol for PJI in our region has enabled mutual understanding, has supported agreement on how to treat specific patients, and has led to clarity for smaller hospitals in our region for when to refer patients without jeopardizing important initial treatment locally. Furthermore, a mutual PJI patient database has enabled the improvement of our protocol, based on medicine-based evidence from our scientific data. In this paper we describe our NINJA protocol