Stepwise implementation of an enhanced recovery pathway for elective total hip arthroplasty in a Swiss hospital: a cohort study.

Background: Enhanced recovery programs after total hip arthroplasty have been shown to reduce hospital length of stay without compromising results, but yet there is a lack of data for the Swiss population. Therefore, this retrospective cohort study evaluated whether similar positive effects on clinical outcomes are present in the context of the Swiss healthcare system.

Methods: Patients who underwent elective primary total hip arthroplasty were analysed.

Functional assessment of total hip arthroplasty using inertial measurement units: Improvement in gait kinematics and association with patient-reported outcome measures.

Inertial measurement units (IMUs) are commonly used for gait assessment, yet their potential for quantifying improvements in gait function and patterns after total hip arthroplasty (THA) has not been fully explored. The primary aim of this study was to compare spatiotemporal parameters and sagittal plane kinematic patterns of patients with hip osteoarthritis (OA) before and after THA, and to asymptomatic controls. The secondary aim was to assess the association between dynamic hip range of motion (ROM) during walking and the Hip Osteoarthritis Outcome Scores (HOOS).

Assessing Site Specificity of Osteoarthritic Gait Kinematics with Wearable Sensors and Their Association with Patient Reported Outcome Measures (PROMs): Knee versus Hip Osteoarthritis.

There is a great need for quantitative outcomes reflecting the functional status in patients with knee or hip osteoarthritis (OA) to advance the development and investigation of interventions for OA. The purpose of this study was to determine if gait kinematics specific to the disease-i.e.

Side to side kinematic gait differences within patients and spatiotemporal and kinematic gait differences between patients with severe knee osteoarthritis and controls measured with inertial sensors.

Background: Kinematic changes associated with knee osteoarthritis (OA) have been traditionally measured with camera-based gait analysis. Lately, inertial sensors have become popular for gait analysis with the advantage of being less time consuming and not requiring a dedicated laboratory.

Research Question: Do spatiotemporal and discrete kinematic gait parameters measured with the inertial sensor system RehaGait® differ between the affected and unaffected side in patients with unilateral knee OA and between patients with severe knee OA and asymptomatic control subjects? Do these differences have a similar magnitude as those reported in the literature?

Methods: Twenty-two patients with unilateral knee OA scheduled for total knee replacement and 46 age matched control subjects were included in this study.

Kinematic changes in severe hip osteoarthritis measured at matched gait speeds.

Kinematic differences between patients with osteoarthritis (OA) and control participants have been reported to be influenced by gait speed. The purpose of this study was to experimentally detect the effect of walking speed on differences in spatiotemporal parameters and kinematic trajectories between patients with hip OA and age-matched asymptomatic participants using wearable sensors and statistical parametric mapping (SPM). Twenty-four patients with severe unilateral hip OA and 48 control participants were included in this study.

Measuring gait kinematics in patients with severe hip osteoarthritis using wearable sensors.

Background: The popularity of inertial sensors in gait analysis is steadily rising. To date, an application of a wearable inertial sensor system for assessing gait in hip osteoarthritis (OA) has not been reported.

Research Question: Can the known kinematic differences between patients with hip OA and asymptomatic control subjects be measured using the inertial sensor system RehaGait®?

Methods: The patients group consisted of 22 patients with unilateral hip OA scheduled for total hip replacement.

Kinematic changes in patients with severe knee osteoarthritis are a result of reduced walking speed rather than disease severity.

Background: Kinematic changes in patients with knee osteoarthritis (OA) have been extensively studied. Concerns have been raised whether the measured spatiotemporal and kinematic alterations are associated with disease progression or merely a result of reduced walking speed.

Research Question: The purpose of this study was to investigate the effect of walking speed on kinematic parameters in patients with knee OA using statistical parametric mapping (SPM).

Is cemented revision total hip arthroplasty a reasonable treatment option in an elderly population?

Revision THA is increasingly performed especially in the elderly population. The surgeon's challenge is to provide a solution that supports immediate full weight-bearing, despite poor bone quality. Shape-closed revision stems facilitate that by combining cement fixation with additional press-fit anchoring.

Five-year prospective subsidence analysis of 100 cemented polished straight stems: A concise clinical and radiological follow-up observation.

Early subsidence (>1.5mm) has been shown to be an indicator for later aseptic loosening of cemented hip stems. For the cemented twinSys stem we published excellent short-term results at 2 years.

Mid-term results of revision total hip arthroplasty with an uncemented modular femoral component.

Introduction: During revision total hip arthroplasty (THA), the surgeon commonly faces deficient proximal femoral bone. In this situation, distal fixation of the prosthesis is required. The aim of the current retrospective study is to assess the clinical and radiographic mid-term outcome of revision total hip arthroplasty using a modular uncemented, tapered, grit-blasted, distal straight stem system.

Excellent long-term results of the Müller acetabular reinforcement ring in primary cup revision.

Background and purpose - The original Müller acetabular reinforcement ring (ARR) was developed to be used for acetabular revisions with small cavitary and/or segmental defects or poor acetabular bone quality. Long-term data for this device are scarce. We therefore investigated long-term survival and radiographic outcome for revision total hip arthroplasty using the ARR.

Rivaroxaban for Thromboprophylaxis After Nonelective Orthopedic Trauma Surgery in Switzerland.

This study investigated the effectiveness and the outcomes of rivaroxaban vs the standard of care for venous thromboembolic prophylaxis in patients undergoing fracture-related surgery. A total of 413 patients undergoing fracture-related surgery from 9 Swiss orthopedic and trauma centers were enrolled. The authors selected the type of venous thromboembolic prophylaxis according to standardized medical practice at the participating centers before the inclusion of patients: 208 patients received rivaroxaban and 205 received the standard of care.

Risk of infection in primary, elective total hip arthroplasty with direct anterior approach or lateral transgluteal approach: a prospective cohort study of 1104 hips.

Background: The direct anterior approach (DAA) is increasingly popular for hip replacement. However, the small incision and the location near to the groin might increase the risk of periprosthetic joint infection (PJI). We asked the questions (i) whether there is an increased risk of infection for this approach, and (ii) whether the spectrum of microorganisms differs between patients with DAA and those with lateral transgluteal approach (LAT).

Eradication of infection, survival, and radiological results of uncemented revision stems in infected total hip arthroplasties.

Background and purpose - The use of uncemented revision stems is an established option in 2-stage procedures in patients with periprosthetic joint infection (PJI) after total hip arthroplasty (THA). However, in 1-stage procedures, they are still rarely used. There are still no detailed data on radiological outcome after uncemented 1-stage revisions.

Prospective two-year subsidence analysis of 100 cemented polished straight stems - a short-term clinical and radiological observation.

Background: Cemented stems show good long-term results and the survival of new implants can be predicted by their early subsidence. With EBRA-FCA (Femoral Component Analysis using Einzel-Bild-Röntgen-Analyse) early subsidence as an early indicator for later aseptic loosening can be analysed. For the cemented TwinSys stem mid- and long-term data is only avalible from the New Zeeland Arthroplasty register, thus close monitoring of this implant system is still mandatory.

Similar effect of stem geometry on radiological changes with 2 types of cemented straight stem: The Müller stem and the Virtec stem compared in 711 hips.

Background And Purpose: There are 2 basic principles in cemented stem fixation: shape-closed and force-closed. We investigated 2 shape-closed straight stems, the Müller (MSS) and the Virtec (VSS), which differ only in geometrical cross section, to determine whether the difference in stem shape would affect the radiological results or long-term survival.

Patients And Methods: We included 711 hips (in 646 patients) that were operated on between July 1996 and July 2003.

Excellent long-term results of the Müller acetabular reinforcement ring in primary total hip arthroplasty: A prospective study on radiology and survival of 321 hips with a mean follow-up of 11 years.

Background And Purpose: The original Müller acetabular reinforcement ring (ARR) shows favorable medium-term results for acetabular reconstruction in total hip arthroplasty, where it is used when the acetabular bone stock is deficient. However, there are no data regarding long-term survival of the device. We therefore investigated long-term survival and analyzed radiological modes of failure.

Metal backed fixed-bearing unicondylar knee arthroplasties using minimal invasive surgery: a promising outcome analysis of 132 cases.

Background: Unicondylar knee arthroplasty (UKA) is a well-established treatment for isolated osteoarthritis (OA) of the medial knee compartment. Aim of this retrospective study was to evaluate the early clinical and radiological outcomes of a consecutive series of patients treated with medial metal backed fixed-bearing UKA. Furthermore, the influence of the component orientation on the outcome was analyzed.

One-stage revision of infected hip arthroplasty: outcome of 39 consecutive hips.

Purpose: There are various options for treating periprosthetic joint infection (PJI). Two-stage exchange has traditionally been the gold standard. However, if the appropriate surgical intervention is chosen according to a rational algorithm, the outcome is similar when using all types of interventions.

Staphylococcal biofilm formation on the surface of three different calcium phosphate bone grafts: a qualitative and quantitative in vivo analysis.

Differences in physico-chemical characteristics of bone grafts to fill bone defects have been demonstrated to influence in vitro bacterial biofilm formation. Aim of the study was to investigate in vivo staphylococcal biofilm formation on different calcium phosphate bone substitutes. A foreign-body guinea-pig infection model was used.

Influence of physico-chemical material characteristics on staphylococcal biofilm formation--a qualitative and quantitative in vitro analysis of five different calcium phosphate bone grafts.

Various compositions of synthetic calcium phosphates (CaP) have been proposed and their use has considerably increased over the past decades. Besides differences in physico-chemical properties, resorption and osseointegration, artificial CaP bone graft might differ in their resistance against biofilm formation. We investigated standardised cylinders of 5 different CaP bone grafts (cyclOS, chronOS (both β-TCP (tricalcium phosphate)), dicalcium phosphate (DCP), calcium-deficient hydroxyapatite (CDHA) and α-TCP).

Approaches for primary total hip replacement.

In total hip replacement surgeons can choose from a various number of approaches, from posterior, lateral or direct anterior. Excellent results can be achieved with all approaches and there is no evidence for the use of a specific approach. Minimally invasive operating techniques might further contribute to that success.