Assessment of patient functional performance in different knee arthroplasty designs during unconstrained squat

Abstract

SummaryBackground: In this paper, squat named by Authors unconstrained because performed without constrains related to feet position, speed, knee maximum angle to be reached, was tested as motor task revealing differences in functional performance after knee arthroplasty. It involves large joints ranges of motion, does not compromise joint safety and requires accurate control strategies to maintain balance. Methods: Motion capture techniques were used to study squat on a healthy control group (CTR) and on three groups, each characterised by a specific knee arthroplasty design: a Total Knee Arthroplasty (TKA), a Mobile Bearing and a Fixed Bearing Unicompartmental Knee Arthroplasty (respectively MBUA and FBUA). Squat was analysed during descent, maintenance and ascent phase and described by speed, angular kinematics of lower and upper body, the Center of Pressure (CoP) trajectory and muscle activation timing of quadriceps and biceps femoris. Results: Compared to CTR, for TKA and MBUA knee maximum flexion was lower, vertical speed during descent and ascent reduced and the duration of whole movement was longer. CoP mean distance was higher for all arthroplasty groups during descent as higher was, CoP mean velocity for MBUA and TKA during ascent and descent. Conclusions: Unconstrained squat is able to reveal differences in the functional performance among control and arthroplasty groups and between different arthroplasty designs. Considering the similarity index calculated for the variables showing statistically significance, FBUA performance appears to be closest to that of the CTR group. Level of evidence: III a.KEY WORDS: angular kinematics, Center of pressure, electromyography, unconstrained squat, unicompartmental knee arthroplasty, total knee arthroplasty.

Fixed- versus mobile-bearing unicompartmental knee arthroplasty: a meta-analysis

“…Differences in clinical outcomes between FB and MB prostheses has been reviewed with each study using different functional measurement indexes. Some studies 15,19 found better results in knee functional scores with the MB group, while Inoue et al 12 and Ozcan et al 11 found higher postoperative KSS in the FB group. Interestingly, Peersman et al 24 demonstrated that there was a tendency for the KSS to deteriorate more rapidly in MB than FB prostheses between 10 and 15 years.…”

“…Two studies 1,20 found similar results between FB and MB groups in respect to pain (p > 0.05), however, Gleeson et al 5 reported that the total pain score, as assessed using the Bristol Knee Score, was significantly greater in the FB group at 2 years (p = 0.013). Postoperative ROM was assessed in five studies 9,12,15,19,20 , no significant difference was shown between the FB and MB groups (p = 0.19; WMD = − 1.53; 95% CI − 3.80 to 0.74).…”

“…Clinical outcomes. Nine studies assessed the Knee Society Score (KSS) 1,[9][10][11][12]15,19,20,22 ; six studies assessed the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score 11,[16][17][18]20,22 ; three studies assessed the Oxford Knee Score (OKS) 5,15,17 ; one study assessed the Italian Orthopedic UKR's Users Group (GIUM) score 9 ; one study assessed the Bristol knee score 5 ; and one study assessed the International Knee Society score 8 . No significant statistical differences were reported between the FB and MB groups on all knee scores measured in these studies.…”

The relation between muscle force and functional movement performance in patients one year after knee replacement surgery: a pilot study

“…However, a recent study, which analyzed the squat movement using a 3D motion capture system, revealed significant differences in functional performance between patients with knee replacement and controls. For instance, a significant difference of 1.5s was found between TKA and controls for the duration of the descending part of the squat, or, a few mm of displacement in center of pressure mean distance has also been reported [17]. These differences can hardly be identified by visual observation alone and require more sophisticated equipment which is not readily available in daily clinical practice.…”

“…Some studies have been performed in the knee arthroplasty population and report a decrease in quadriceps activity and an increase in hamstring activation patterns during a squat, which lead to postural deviations in both the sagittal and the frontal plane. These deviations also resulted in an asymmetric transfer of the body weight to the lower limbs [17]. Nonetheless, it was demonstrated that TKA patients gradually evolve towards a more symmetrical loading of both knees as rehabilitation sessions progress.…”