Baseline Gait Muscle Activation Patterns Differ for Osteoarthritis Patients Who Undergo Total Knee Arthroplasty Five to Eight Years Later From Those Who Do Not

Abstract

Objective. To determine if baseline quadriceps and hamstrings muscle activity patterns differed between those with medial-compartment knee osteoarthritis (OA) who advanced to total knee arthroplasty (TKA) and those who did not advance to TKA, and to examine associations between features extracted from principal component analysis (PCA) and discrete measures. Methods. Surface electromyograms of the vastus lateralis and medialis, rectus femoris, and lateral and medial hamstrings during walking were collected from 54 individuals with knee OA. Amplitude and temporal characteristics from PCA, co-contraction indices (CCI) for lateral and medial muscle pairs, and root mean square (RMS) amplitudes for early, mid, late, and overall stance were calculated from electromyographic waveforms. At follow-up 5 to 8 years later, 26 participants reported having undergone TKA. Analysis of variance models tested for differences in principal component (PC) scores and discrete measures between TKA and no-TKA groups (α = 0.05). Pearson's product moment correlation coefficients were calculated between PC scores and discrete variables. Results. The TKA group had higher hamstrings activity magnitudes (PC1), prolonged activity in mid stance (PC2) for all muscles, and greater lateral CCI. TKA had higher RMS hamstrings activity for all stance phases, and higher RMS mid-and late-stance quadriceps activity. PC1 was highly correlated with RMS amplitude (highest overall and early stance). PC2 was correlated with mid-and late-stance RMS. CCIs were correlated with PC1 and PC2, with greater variance explained for PC1. Conclusion. Those who advanced to TKA had higher magnitudes and more prolonged agonist and antagonist activity, consistent with less joint unloading. These gait muscle activation patterns indicate a potential conservative intervention target.

A new integrated behavioural intervention for knee osteoarthritis: development and pilot study

“…Biomechanical studies have investigated the potential effects of muscle overactivity, typically quantifying this phenomenon using a co-contraction index [ 19 ]. Increased co-contraction has been linked to increased pain [ 20 ], elevated joint load [ 21 ], a more rapid rate of cartilage loss [ 22 ] and an increase in the likelihood that patients will opt for a knee replacement at 5-year follow up [ 23 ]. Given these findings, muscle overactivity is likely to increase the mechanical stress on the articular surface, the bone, joint capsule and periarticular structures and therefore may increase nociceptive input, exacerbating pain [ 24 ].…”

The effect of increasing trunk flexion during normal walking

“…Modelling studies have demonstrated a clear peak in joint loading during early stance [13] and also shown that elevated muscle activity, during this period, will increase contact force [13,14]. Other related research has shown that elevated muscle activity during the early stance period will accelerate cartilage loss [15] and increase the likelihood of progression to knee arthroplasty [16]. It is therefore critical to understand the mechanisms which underlie elevated muscle activity, in people with knee osteoarthritis, during early stance.…”

Tension Release Therapy: The Development of a New Integrated Behavioural Intervention for Knee Osteoarthritis

“…Elevated co-contraction will increase stress on the articular surface, on the bone, joint capsule and periarticular structures, and is likely to increased pain [34]. These ndings indicate that co-contraction could be a potential intervention target [33].…”

“…Whereas in a healthy person these muscles activate sequentially during walking, in individuals with knee OA these muscles contract simultaneously during the stance phase of gait. Recent studies have demonstrated the potentially damaging effect of these patterns, showing that increased co-contraction will increase the compressive loads on the joint surface [31], speed up the rate of cartilage loss [32] and increase the likelihood that patients will opt for a knee replacement at 5-year follow up [33]. Elevated co-contraction will increase stress on the articular surface, on the bone, joint capsule and periarticular structures, and is likely to increased pain [34].…”

“…In line with this idea, it is possible that muscle co-contraction may function to improve knee stability following acute injury [47]. However, increases in knee muscle co-contraction have been associated with increased contact force [67], accelerated loss of articular cartilage [32] and poor long-term clinical outcomes [33]. Therefore, it would appear to be a maladaptive motor response if maintained in the long term.…”