Dataset Information

Dynamic RSA for the evaluation of inducible micromotion of Oxford UKA during step-up and step-down motion.

ABSTRACT: Background and purpose - Implant inducible micromotions have been suggested to reflect the quality of the fixation interface. We investigated the usability of dynamic RSA for evaluation of inducible micromotions of the Oxford Unicompartmental Knee Arthroplasty (UKA) tibial component, and evaluated factors that have been suggested to compromise the fixation, such as fixation method, component alignment, and radiolucent lines (RLLs). Patients and methods - 15 patients (12 men) with a mean age of 69 (55-86) years, with an Oxford UKA (7 cemented), were studied after a mean time in situ of 4.4 (3.6-5.1) years. 4 had tibial RLLs. Each patient was recorded with dynamic RSA (10 frames/second) during a step-up/step-down motion. Inducible micromotions were calculated for the tibial component with respect to the tibia bone. Postoperative component alignment was measured with model-based RSA and RLLs were measured on screened radiographs. Results - All tibial components showed inducible micromotions as a function of the step-cycle motion with a mean subsidence of up to -0.06?mm (95% CI: -0.10 to -0.03). Tibial component inducible micromotions were similar for cemented fixation and cementless fixation. Patients with tibial RLLs had 0.5° (95% CI: 0.18-0.81) greater inducible medio-lateral tilt of the tibial component. There was a correlation between postoperative posterior slope of the tibial plateau and inducible anterior-posterior tilt. Interpretation - All patients had inducible micromotions of the tibial component during step-cycle motion. RLLs and a high posterior slope increased the magnitude of inducible micromotions. This suggests that dynamic RSA is a valuable clinical tool for the evaluation of functional implant fixation.

SUBMITTER: Horsager K

PROVIDER: S-EPMC5434595 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Dynamic RSA for the evaluation of inducible micromotion of Oxford UKA during step-up and step-down motion.

Horsager Kristian K Kaptein Bart L BL Rømer Lone L Jørgensen Peter B PB Stilling Maiken M

Acta orthopaedica 20170109 3

Background and purpose - Implant inducible micromotions have been suggested to reflect the quality of the fixation interface. We investigated the usability of dynamic RSA for evaluation of inducible micromotions of the Oxford Unicompartmental Knee Arthroplasty (UKA) tibial component, and evaluated factors that have been suggested to compromise the fixation, such as fixation method, component alignment, and radiolucent lines (RLLs). Patients and methods - 15 patients (12 men) with a mean age of 6 ...[more]

PMID: 28067099

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Project description:BackgroundMental health Step-up, Step-down services (SUSD), also known as subacute services or Prevention and Recovery Services, have emerged to fill an identified gap between hospital-based inpatient care and clinical community-based mental health support. Evidence for the effectiveness of the SUSD service model is limited but growing. Accordingly, this study looked to add to the extant body of knowledge, by (i) assessing change outcomes in mental health and wellbeing, and predictors of these changes, for patients who accessed Western Australia's first SUSD service; and (ii) evaluating patients' satisfaction with service, and what patients value from their stay.MethodsThis was a mixed-method retrospective cohort study. Participants comprised 382 patients who accessed a 22-bed Mental Health SUSD facility and incurred 551 episodes of care during the 01/07/2014-30/06/2016 period. Patients' change outcomes in psychological distress, general self-efficacy, and work and social adjustment from service entry to service exit were analyzed using generalized linear modeling. Simple Pearson's correlation coefficients were calculated for preliminary assessment of the associations between patients' service satisfaction and their change outcomes. Qualitative outcomes that patients valued from their stay were analyzed thematically according to a semi-grounded theoretical approach.ResultsSignificant improvements were observed in patients' self-reported psychological distress, self-efficacy, and work and social adjustment (all p?<?0.0001). A strong and persistent baseline effect existed across the three measures. Older age, female gender, and having a dependent child in the same household were protective/enhancing factors for the patients' recovery. Satisfaction with service was high. Patients valued having the time and space to recuperate, gain insight, focus, and create changes in their lives.ConclusionThe encouraging findings, regarding both patients' change outcomes and satisfaction with service, support the value of the SUSD service model for patients with mental illnesses. Strengths and limitations were discussed; ensued recommendations were offered to both service providers and researchers to enhance the robustness of future research findings, to help inform more effective policy and funding decisions related to mental health care.

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Dataset Information

Dynamic RSA for the evaluation of inducible micromotion of Oxford UKA during step-up and step-down motion.

Publications

Dynamic RSA for the evaluation of inducible micromotion of Oxford UKA during step-up and step-down motion.

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