Central sensitization inventory scores correlate with pain at rest in patients with hip osteoarthritis: a retrospective study

Abstract

Background: Patients with persistent pain due to osteoarthritis (OA) complain of multiple symptoms that cannot be explained solely by structural changes. A poor correlation exists between structural and inflammatory changes in OA and pain levels. Central sensitization (CS) has been identified as a factor that induces chronic pain in patients with OA. Although it is important to identify osteoarthritis patients with CS components, the prevalence and characteristics of CS, especially those in patients with hip OA, are not well understood. Thus, we aimed to determine the prevalence and characteristics of CS in patients with hip OA, in this study. Methods: The CS Inventory (CSI), used as a non-invasive routine clinical tool to evaluate the presence of CS 1 month before surgery in 100 patients with hip OA, was measured at our outpatient clinic, and the data were retrospectively reviewed. We determined the number of patients with a CSI score of 40 points or higher and assessed the relationships between the CSI score and clinical factors (including age, duration of hip pain, degree pain at rest and on activity, by using the visual analogue scale [VAS] and the Harris Hip Score) using the Spearman's correlation coefficient. Results: The mean age of participants was 63.9 ± 11.6 years, and there were 15 men and 85 women. All patients had hip OA, categorised as advanced and terminal stage (Tönnis grade 2-3) on preoperative plain radiography. The mean duration of hip pain was 4.2 ± 4.4 years. The mean CSI score was 19.5 ± 11.3 and 5 (5.0%) of the patients had a score of 40 or more points. CSI scores correlated significantly only with VAS pain at rest (r = 0.348, P < 0.001). Conclusion: In this study, 1 out of every 20 hip OA patients had CS components. CSI scores were significantly correlated with pain at rest in hip OApatients. CS approaches to hip OA may be one of the treatment options for pain at rest.

NGF Expression and Elevation in Hip Osteoarthritis Patients with Pain and Central Sensitization

“…The CSI was established as a screening tool to help clinicians identify patients with central sensitivity syndrome, in which CS may be a root etiology. Previous studies have used the CSI to study the association of pain with CS components in patients with kOA and hOA [ 4 , 16 , 17 ]. In this study, we asked patients to complete the CSI to assess whether they exhibit CS components.…”

“…Further, individuals exhibiting pain and CS components are resistant to conservative treatment, including nonsteroidal anti-inflammatory drugs (NSAIDs) and other pain medication [ 3 ]. We previously reported that 5% of hip OA (hOA) patients have a CS component [ 4 ]. However, the mechanisms underlying CS in hOA are not well understood.…”

Adverse Effects of Higher Preoperative Pain at Rest, a Central Sensitization-Related Symptom, on Outcomes After Total Hip Arthroplasty in Patients with Osteoarthritis

“…We assessed pain at rest and on activity separately, based on our previous study. 9 Pain during walking on level ground was assessed as pain on activity in this study. Furthermore, the participants’ pain at rest and on activity could be a minimum of 0 mm and a maximum of 100 mm.…”

“… 7 In recent years, the CSI has been used to evaluate CS components in patients with hip and knee OA. 8 , 9 Studies using the CSI have indicated that the presence of preoperative CS components in patients with knee OA has a negative impact on postoperative outcomes, such as residual persistent pain, worsening patient satisfaction, and decreased quality of life. 10 , 11 However, to the best of our knowledge, no study has evaluated the relationship between the CSI score and postoperative outcomes in patients with hip OA who underwent THA.…”

“… 14 , 15 We previously reported a correlation between the presence of CS components and the level of pain at rest in patients with hip OA. 9 Therefore, pain at rest may reflect the presence of CS and be a predictor of the postoperative outcomes. However, it remains unclear whether CS is one of the causes of exacerbated pain at rest and whether pain at rest affects the postoperative outcomes because our previous study was a univariable analysis of preoperative clinical scores.…”