Pain, sensitization and physical performances in patients with chronic painful knee osteoarthritis or chronic pain following total knee arthroplasty: An explorative study

Abstract

Background: The aim of this study was to assess clinical pain, pain sensitization and physical performances to profile patients with chronic painful knee osteoarthritis (OA) or pain after total knee arthroplasty (TKA). Examining the interactions between pain mechanisms and physical performances would enable us to investigate the underlying explanatory relationships between these parameters. Methods: In this explorative study, 70 patients with chronic painful knee OA (N = 46) or chronic pain after TKA (N = 24) were assessed for clinical pain, quantitative sensory profiling (mechanical pinprick pain sensitivity, temporal summation (TS) and conditioned pain modulation), physical performances (chair stand, walk and stair climb tests) and self-reported outcomes. Between-group comparisons were made using ANCOVA tests and associations between outcomes were analysed using multivariate linear regression models. Results: Overall, no differences between groups regarding clinical pain and quantitative sensory profiling outcomes were observed. Physical performances were lower in the TKA group compared with the OA group with moderate-to-large effect sizes, and a tendency towards better scores in self-reported outcomes for the OA group was observed with small-to-moderate effect sizes. Self-reported function seems to be associated with physical performances in the TKA group. Sensitization (TS) appears to be associated with poorer physical performances in the OA group. Conclusions: Similar profiles for pain intensity, signs of sensitization and conditioned pain modulation were observed. Patients with TKA seems to have impaired physical performances compared with the OA group, underlining the importance of targeting physical performances. Only the OA patients showed an association between sensitization (TS) and physical performance. Significance: Quantitative pain profiling assessment was used to assess pain intensities and pain mechanisms. We observed associations between physical performances and temporal summation in the OA group underlining the importance of assessing motor functions and pain mechanisms in the same trial. We observed lower levels of physical performances in the TKA group compared with the OA group, suggesting that examination and rehabilitation of physical performances is essential for TKA patients with chronic pain. 214 | BIE LARSEN Et AL.

TGF-β1 in plasma and cerebrospinal fluid can be used as a biological indicator of chronic pain in patients with osteoarthritis

“…For example, underlying diseases such as arthritis are usually associated with chronic pain for weeks or even months [2]. In patients with osteoarthritis (OA), chronic pain persists due to the progression of the disease and becomes a disabling symptom of OA [3]. Therefore, selection of pain control agents and finding the relevant biological indicators are important in the treatment of OA.…”

Subgrouping of facilitatory or inhibitory conditioned pain modulation responses in patients with chronic knee pain. Explorative analysis from a multicentre trial

“…Conditioned pain modulation and temporal summation have been proposed to be part of central pain amplification processes related to pain sensitization (Arendt-Nielsen et al, 2010), possibly explaining the observed association in the facilitatory CPM group (Fingleton et al, Other studies have failed to find associations between CPM, sensitization and pain outcomes (Cardoso et al, 2016;Carlesso et al, 2022). However, these studies did not take the individual variation in CPM responses into account as suggested necessary in our recent studies (Arendt-Nielsen et al, 2020;Bie Larsen et al, 2020;Sachau et al, 2022). Our findings illustrate that subgrouping of patients according to their CPM responses can be essential to gain an insight into a chronic knee pain population with considerable variation in CPM responses (Bie Larsen et al, 2020).…”

“…Based on the explorative design and the purpose of evaluating associations, no primary outcome was chosen. However, several outcomes of interest were included, possibly characterizing different traits of chronic pain from knee OA or following TKA (Bie Larsen et al, 2020). The outcomes of interest were CPM, pain intensity, movement‐evoked pain intensity, temporal summation, widespread pain, self‐reported physical function, presence of neuropathic pain, pain interference and pain qualities.…”

“…In human volunteer studies, the CPM effect depends on different test paradigms, for example using heat, cold, electrical or pressure as test and conditioning stimuli (Fernandes et al, 2019; Vaegter et al, 2018). Substantial variations have been found within and across studies (Arendt‐Nielsen et al, 2020; Bie Larsen et al, 2020; Cummins et al, 2020; Hermans et al, 2016; Kennedy et al, 2016; Schliessbach et al, 2019).…”

“…Studies have shown that the CPM potency is highly variable and that chronic pain populations consist of patients with both facilitatory and inhibitory CPM responses (Bie Larsen et al, 2020; Teixeira et al, 2020; Teles et al, 2019). At present, the possible information provided by the CPM variation is not fully understood, despite the effort to investigate, for instance, CPM responders and non‐responders (Potvin & Marchand, 2016) using different stimulation paradigms (Oono et al, 2011).…”