Dosing and treatment duration of suppressive antimicrobial therapy in orthopedic implant infections: a cohort study.

Introduction: Limited data inform about the optimal dosing and duration of suppressive antimicrobial therapy (SAT) for orthopedic implant infection (OII). We aimed to compare the effectiveness of low-dosage with standard-dosage SAT and evaluate the safety of stopping SAT. Methods: All patients with OII treated with SAT from 2011 to 2022 were retrospectively included. Data were extracted from electronic patient files. Low-dosage SAT was defined as antimicrobial therapy dosed lower than the standard dosage recommended for OII. The association of dosing strategy and other factors with failure-free survival were assessed by Kaplan-Meier and Cox proportional hazard models. Results: One-hundred-and-eight patients were included. The median follow-up time after SAT initiation was 21 months (interquartile range (IQR) 10-42 months). SAT was successful in 74 patients (69 %). Low-dosage SAT ( n = 82 ) was not associated with failure in univariate (hazard ratio (HR) 1.23, 95 % confidence interval (CI) 0.53-2.83) and multivariate analyses (HR 1.24, 95 % CI 0.54-2.90). In 25 patients (23 %), SAT was stopped after a median treatment duration of 26 months. In this group, one patient (4 %) developed a relapse. Conclusions: In this study, low-dosage SAT was as effective as standard dosage SAT. Moreover, stopping SAT after 2 to 3 years may be justified in patients with a good clinical course. These findings warrant further research on optimal dosing and duration of SAT and on the durability of in vivo biofilms.

An innovative care model coordinated by a physical therapist and nurse practitioner for osteoarthritis of the hip and knee in specialist care: a prospective study.

The subject of the study is to investigate whether health-related quality of life (HRQoL), pain and function of patients with hip or knee osteoarthritis (OA) improves after a specialist care intervention coordinated by a physical therapist and a nurse practitioner (NP) and to assess satisfaction with this care at 12 weeks. This observational study included all consecutive patients with hip or knee OA referred to an outpatient orthopaedics clinic. The intervention consisted of a single, standardized visit (assessment and individually tailored management advice, to be executed in primary care) and a telephone follow-up, coordinated by a physical therapist and a NP, in cooperation with an orthopaedic surgeon. Assessments at baseline and 10 weeks thereafter included the short form-36 (SF-36), EuroQol 5D (EQ-5D), hip or knee disability and osteoarthritis outcome score (HOOS or KOOS), the intermittent and constant osteoarthritis pain questionnaire (ICOAP) for hip or knee and a multidimensional satisfaction questionnaire (23 items; 4 point scale). Eighty-seven patients (57 female), mean age 68 years (SD 10.9) were included, with follow-up data available in 63 patients (72 %). Statistically significant improvements were seen regarding the SF-36 physical summary component score, the EQ-5D, the ICOAP scores for hip and knee, the HOOS subscale sports and the KOOS subscales pain, symptoms and activities of daily living. The proportions of patients reporting to be satisfied ranged from 79 to 98 % per item. In patients with hip and knee OA pain, function and HRQoL improved significantly after a single-visit multidisciplinary OA management intervention in specialist care, with high patient satisfaction.

Muscle characteristics in patients with chronic systemic inflammation.

INTRODUCTION: Histological characteristics of age-related muscle wasting are type II muscle fiber atrophy, accumulation of oxidative stress-induced lipofuscin granules and decreased satellite cell numbers. There is increasing clinical evidence for a strong correlation between chronic systemic inflammation and age-related muscle wasting. The aim of this study was to determine the impact of chronic systemic inflammation on age-related histological muscle characteristics. METHODS: As a model for chronic systemic inflammation, we included 10 patients suffering from rheumatoid arthritis (RA) and 27 control patients suffering from osteoarthritis (OA). Biopsies were taken from the vastus medialis muscle. RESULTS: No significant differences were found in type II muscle fiber atrophy, lipofuscin accumulation, or satellite cell number in RA compared with OA patients. CONCLUSIONS: These results suggest there is no association between chronic systemic inflammation in RA and age-related muscle characteristics. Future research should focus on inflammation and satellite cell function.

Integrated assessment techniques for linking kinematics, kinetics and muscle activation to early migration: a pilot study.

The goal of this pilot study was to develop and test an integrated method to assess kinematics, kinetics and muscle activation of total knee prostheses during dynamic activities, by integrating fluoroscopic measurements with force plate, electromyography and external motion registration measurements. Subsequently, this multi-instrumental analysis was then used to assess the relationship between kinematics, kinetics and muscle activation and early migration of the tibial component of total knee prostheses. This pilot study showed that it is feasible to integrate fluoroscopic, kinematic and kinetic measurements and relate findings to early migration data. Results showed that there might be an association between deviant kinematics and early migration in patients with a highly congruent mobile-bearing total knee prosthesis. Patients that showed high levels of coactivation, diverging axial rotations of the insert and a deviant pivot point showed increased migration and might be at higher risk for tibial component loosening. In the future, to confirm our findings, the same integrated measurements have to be performed in larger patient groups and different prosthesis designs.