Are there functional biomechanical differences in robotic arm-assisted bi-unicompartmental knee arthroplasty compared with conventional total knee arthroplasty? A prospective, randomized controlled trial

Long-term gait analysis in patients after total knee arthroplasty: A systematic review and meta-analysis

BACKGROUND

Gait abnormalities have been described in patients after total knee arthroplasty (TKA), leading to the development of inter-joint coordination abnormalities and increased risk of falling. Such impairments have been reported to persist in the long-term, although the majority of studies assessed gait pattern especially in the first months after TKA.

RESEARCH QUESTION

What are the long-term gait impairments in patients after TKA compared to healthy age-matched subjects?

METHODS

A systematic search was conducted on MEDLINE/PubMed, EMBASE, CENTRAL and Scopus databases. Observational studies or randomized controlled trials investigating gait spatial-temporal, kinematic and kinetics parameters in a time-window longer than 6 months in patients with TKA compared to healthy age-matched subjects were included. Methodological quality was assessed using the modified Downs and Black (D&B) checklist and participants' characteristics, surgical procedures details and outcome measures were extracted. Pooled or un-pooled findings were categorized into "6 months - 1 year" and "more than 1 year" timepoint categories.

RESULTS

Twenty-eight studies (976 patients) were included. Overall quality was fair with a mean modified D&B score of 63.5 %. Reduced speed, stride length, cadence and longer stance phase were found in patients when compared to healthy individuals at "6 months - 1 year" follow-up. Spatial-temporal parameters deficits were also found at more than 1 year after TKA, where lower single-limb support and longer double-limb support durations were detected. These impairments occurred in concomitance with decreased knee range of motion along the sagittal and frontal planes and altered kinetic parameters. Hip kinematic and kinetic long-term impairments were also detected after TKA.

SIGNIFICANCE

These findings highlighted long-term gait pattern alterations in patients with TKA compared to age-matched healthy subjects. Future studies should identify interventions able to reduce long-term gait pattern alterations and improve function in patients after TKA.

Osteoarthritis year in review 2023: Biomechanics

Biomechanics plays a significant yet complex role in osteoarthritis (OA) onset and progression. Identifying alterations in biomechanical factors and their complex interactions is critical for gaining new insights into OA pathophysiology and identification of clearly defined and modifiable mechanical treatment targets. This review synthesized biomechanics studies from March 2022 to April 2023, from which three themes relating to human gait emerged: (1) new insights into the pathogenesis of OA using computational modeling and machine learning, (2) technology-enhanced biomechanical interventions for OA, and (3) out-of-lab biomechanical assessments of OA. We further highlighted future-focused areas which may continue to advance the field of biomechanics in OA, with a particular emphasis on exploiting technology to understand and treat biomechanical mechanisms of OA outside the laboratory. The breadth of studies included in this review highlights the complex role of biomechanics in OA and showcase numerous innovative and outstanding contributions to the field. Exciting cross-disciplinary efforts integrating computational modeling, mobile sensors, and machine learning methods show great promise for streamlining in vivo multi-scale biomechanics workflows and are expected to underpin future breakthroughs in the understanding and treatment of biomechanics in OA.

Reliability and validity of pose estimation algorithm for measurement of knee range of motion after total knee arthroplasty

We aimed to assess the reliability and validity of OpenPose, a posture estimation algorithm, for measurement of knee range of motion after total knee arthroplasty (TKA), in comparison to radiography and goniometry. In this prospective observational study, we analyzed 35 primary TKAs (24 patients) for knee osteoarthritis. We measured the knee angles in flexion and extension using OpenPose, radiography, and goniometry. We assessed the test-retest reliability of each method using intraclass correlation coefficient (1,1). We evaluated the ability to estimate other measurement values from the OpenPose value using linear regression analysis. We used intraclass correlation coefficients (2,1) and Bland-Altman analyses to evaluate the agreement and error between radiography and the other measurements. OpenPose had excellent test-retest reliability (intraclass correlation coefficient (1,1) = 1.000). The R² of all regression models indicated large correlations (0.747 to 0.927). In the flexion position, the intraclass correlation coefficients (2,1) of OpenPose indicated excellent agreement (0.953) with radiography. In the extension position, the intraclass correlation coefficients (2,1) indicated good agreement of OpenPose and radiography (0.815) and moderate agreement of goniometry with radiography (0.593). OpenPose had no systematic error in the flexion position, and a 2.3° fixed error in the extension position, compared to radiography. OpenPose is a reliable and valid tool for measuring flexion and extension positions after TKA. It has better accuracy than goniometry, especially in the extension position. Accurate measurement values can be obtained with low error, high reproducibility, and no contact, independent of the examiner's skills.